How do I change the widgets width?

Hi, this is the widget that´s always falling down to the bottom of my sidebar:

Someone told me I have to change it´s size, but I can´t figure out how. I don´t speak HTML…

<!-- Begin MailChimp Signup Form -->
<link href="http://cdn-images.mailchimp.com/embedcode/classic-081711.css" rel="stylesheet" type="text/css">
<style type="text/css">
	#mc_embed_signup{background:#fff; clear:left; font:14px Helvetica,Arial,sans-serif; }
	/* Add your own MailChimp form style overrides in your site stylesheet or in this style block.
	   We recommend moving this block and the preceding CSS link to the HEAD of your HTML file. */
</style>
<div id="mc_embed_signup">
<form action="http://thehealthgladiator.us6.list-manage.com/subscribe/post?u=0c3549a211390de4de66cd037&id=508a7858d9" method="post" id="mc-embedded-subscribe-form" name="mc-embedded-subscribe-form" class="validate" target="_blank" novalidate>
	<h2>Subscribe to our mailing list</h2>
<div class="indicates-required"><span class="asterisk">*</span> indicates required</div>
<div class="mc-field-group">
	<label for="mce-EMAIL">Email Address  <span class="asterisk">*</span>
</label>
	<input type="email" value="" name="EMAIL" class="required email" id="mce-EMAIL">
</div>
<div class="mc-field-group">
	<label for="mce-FNAME">First Name  <span class="asterisk">*</span>
</label>
	<input type="text" value="" name="FNAME" class="required" id="mce-FNAME">
</div>
	<div id="mce-responses" class="clear">
		<div class="response" id="mce-error-response" style="display:none"></div>
		<div class="response" id="mce-success-response" style="display:none"></div>
	</div>	<div class="clear"><input type="submit" value="Subscribe" name="subscribe" id="mc-embedded-subscribe" class="button"></div>
</form>
</div>
<script type="text/javascript">
var fnames = new Array();var ftypes = new Array();fnames[0]='EMAIL';ftypes[0]='email';fnames[1]='FNAME';ftypes[1]='text';fnames[2]='LNAME';ftypes[2]='text';
try {
    var jqueryLoaded=jQuery;
    jqueryLoaded=true;
} catch(err) {
    var jqueryLoaded=false;
}
var head= document.getElementsByTagName('head')[0];
if (!jqueryLoaded) {
    var script = document.createElement('script');
    script.type = 'text/javascript';
    script.src = 'http://ajax.googleapis.com/ajax/libs/jquery/1.4.4/jquery.min.js';
    head.appendChild(script);
    if (script.readyState && script.onload!==null){
        script.onreadystatechange= function () {
              if (this.readyState == 'complete') mce_preload_check();
        }
    }
}
var script = document.createElement('script');
script.type = 'text/javascript';
script.src = 'http://downloads.mailchimp.com/js/jquery.form-n-validate.js';
head.appendChild(script);
var err_style = '';
try{
    err_style = mc_custom_error_style;
} catch(e){
    err_style = '#mc_embed_signup input.mce_inline_error{border-color:#6B0505;} #mc_embed_signup div.mce_inline_error{margin: 0 0 1em 0; padding: 5px 10px; background-color:#6B0505; font-weight: bold; z-index: 1; color:#fff;}';
}
var head= document.getElementsByTagName('head')[0];
var style= document.createElement('style');
style.type= 'text/css';
if (style.styleSheet) {
  style.styleSheet.cssText = err_style;
} else {
  style.appendChild(document.createTextNode(err_style));
}
head.appendChild(style);
setTimeout('mce_preload_check();', 250);

var mce_preload_checks = 0;
function mce_preload_check(){
    if (mce_preload_checks>40) return;
    mce_preload_checks++;
    try {
        var jqueryLoaded=jQuery;
    } catch(err) {
        setTimeout('mce_preload_check();', 250);
        return;
    }
    try {
        var validatorLoaded=jQuery("#fake-form").validate({});
    } catch(err) {
        setTimeout('mce_preload_check();', 250);
        return;
    }
    mce_init_form();
}
function mce_init_form(){
    jQuery(document).ready( function($) {
      var options = { errorClass: 'mce_inline_error', errorElement: 'div', onkeyup: function(){}, onfocusout:function(){}, onblur:function(){}  };
      var mce_validator = $("#mc-embedded-subscribe-form").validate(options);
      $("#mc-embedded-subscribe-form").unbind('submit');//remove the validator so we can get into beforeSubmit on the ajaxform, which then calls the validator
      options = { url: 'http://thehealthgladiator.us6.list-manage2.com/subscribe/post-json?u=0c3549a211390de4de66cd037&id=508a7858d9&c=?', type: 'GET', dataType: 'json', contentType: "application/json; charset=utf-8",
                    beforeSubmit: function(){
                        $('#mce_tmp_error_msg').remove();
                        $('.datefield','#mc_embed_signup').each(
                            function(){
                                var txt = 'filled';
                                var fields = new Array();
                                var i = 0;
                                $(':text', this).each(
                                    function(){
                                        fields[i] = this;
                                        i++;
                                    });
                                $(':hidden', this).each(
                                    function(){
                                        var bday = false;
                                        if (fields.length == 2){
                                            bday = true;
                                            fields[2] = {'value':1970};//trick birthdays into having years
                                        }
                                    	if ( fields[0].value=='MM' && fields[1].value=='DD' && (fields[2].value=='YYYY' || (bday && fields[2].value==1970) ) ){
                                    		this.value = '';
									    } else if ( fields[0].value=='' && fields[1].value=='' && (fields[2].value=='' || (bday && fields[2].value==1970) ) ){
                                    		this.value = '';
									    } else {
									        if (/\[day\]/.test(fields[0].name)){
    	                                        this.value = fields[1].value+'/'+fields[0].value+'/'+fields[2].value;
									        } else {
    	                                        this.value = fields[0].value+'/'+fields[1].value+'/'+fields[2].value;
	                                        }
	                                    }
                                    });
                            });
                        return mce_validator.form();
                    },
                    success: mce_success_cb
                };
      $('#mc-embedded-subscribe-form').ajaxForm(options);

    });
}
function mce_success_cb(resp){
    $('#mce-success-response').hide();
    $('#mce-error-response').hide();
    if (resp.result=="success"){
        $('#mce-'+resp.result+'-response').show();
        $('#mce-'+resp.result+'-response').html(resp.msg);
        $('#mc-embedded-subscribe-form').each(function(){
            this.reset();
    	});
    } else {
        var index = -1;
        var msg;
        try {
            var parts = resp.msg.split(' - ',2);
            if (parts[1]==undefined){
                msg = resp.msg;
            } else {
                i = parseInt(parts[0]);
                if (i.toString() == parts[0]){
                    index = parts[0];
                    msg = parts[1];
                } else {
                    index = -1;
                    msg = resp.msg;
                }
            }
        } catch(e){
            index = -1;
            msg = resp.msg;
        }
        try{
            if (index== -1){
                $('#mce-'+resp.result+'-response').show();
                $('#mce-'+resp.result+'-response').html(msg);
            } else {
                err_id = 'mce_tmp_error_msg';
                html = '<div id="'+err_id+'" style="'+err_style+'"> '+msg+'</div>';

                var input_id = '#mc_embed_signup';
                var f = $(input_id);
                if (ftypes[index]=='address'){
                    input_id = '#mce-'+fnames[index]+'-addr1';
                    f = $(input_id).parent().parent().get(0);
                } else if (ftypes[index]=='date'){
                    input_id = '#mce-'+fnames[index]+'-month';
                    f = $(input_id).parent().parent().get(0);
                } else {
                    input_id = '#mce-'+fnames[index];
                    f = $().parent(input_id).get(0);
                }
                if (f){
                    $(f).append(html);
                    $(input_id).focus();
                } else {
                    $('#mce-'+resp.result+'-response').show();
                    $('#mce-'+resp.result+'-response').html(msg);
                }
            }
        } catch(e){
            $('#mce-'+resp.result+'-response').show();
            $('#mce-'+resp.result+'-response').html(msg);
        }
    }
}

</script>
<!--End mc_embed_signup-->

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