While I worked at QVC, I was involved with a lot with the photography team. We would have to think up new ways to help sell their fashion labels while staying on brand with the TV guidelines.
I have used my skills in design to help grow a lot of different social media channels. The two most visual channels I find are twitter and Instagram. It's important to research what is working and engaging with your target audience. One way to do this is to test and refine based on how your audience interacts with your posts.
When I create a website or work on an established website, there are always the requirements for banners. It can help keep your website fresh and the people who visit will often engage with good design. I have made many banners and sliders for different companies. Its an enjoyable job and it is important that your images degrade nicely for mobile devices as well as scale up for the desktop.
When I left university my first real design job was to help do some promotional work for a local festival in my home town Rhythm and Vines. After attending the event a few times, I decided to start my own T-shirt design and sell them on red bubble. It works quite well and something I still do from time to time.