I work as a Freelancer Software Engineer, usually around the web: PrestaShop modules, eCommerce solutions, small web services, introduction/portfolio websites with extra features (for example: price calculator with order form).
I usually do backend (coding, implementing, server-side scripting, database design, etc.) stuff. I have a friend as a colleague, who is talented in frontend related task (html, js, jquery, css) and we like to exchange work to improve speed and quality.
I try to make my code easy to read, and modifiable. If the task requires, I make some tests for myself (php unit, selenium), to make sure nothing gets broken.