How do I change the font size and color

Can you please provide a link to the website?

Alright and you’re wanting to change the title/menu fonts in the sidebar (currently orange links on left hand side) or some other place in the theme?

I would first suggest creating a child theme – http://codex.wordpress.org/Child_Themes so that your updates won’t get overwritten when a new version of your theme comes out.

Once you have created a child theme, visit Appearance->Editor in the admin area and on the right hand side select style.css from the list of files. When that page is loaded place the following line of code into the content area.

.widget_nav_menu li a {
    color: red;
    font: normal 16px Tahoma;
}

This will change the color of the links to red as well as increasing the font size and switching the font to Tahoma. You can play around with the settings to determine what you like the best.