Upload the AnonPost plugin to your blog, activate it, then edit this plugin to select options you want to use.
Options are located in the beginning of the anonpost.php file.
List of options:
- $anonUserName = 'Anonymous'; // 'name' of anonymous user, doesn't have to exist
- $enableComments = false; // this option enables comments under anonymous posts, set to true/false
- $category = array(); //this array should contain IDs for categories you want anonymous post to be in, example: array(1,2,4). NOTE: create those categories first
- $captchaEnabled = true; // enable reCAPTCHA (set to: true/false)
- $publickey = ''; // enter your API keys here
- $privatekey = '';
- $allowAnonComments = 'true' // if set to true this option will be using [Anonymous Comments](http://wordpress.org/extend/plugins/anon-comments/) plugin for writing comments (remember to install it first, else comments will be closed)
(other options are explained in file itself)