One of my favorite resources for self improvement is Lynda.com.
It’s a subscription website where you watch topical improvement videos.
It’s where I learned Illustrator and Photoshop and a place I’ve gone to soak up knowledge on video production.
I really feel like effective content marketing requires some lightweight design skills (see Matthew Wesson of Pardot’s work). In order to get here, most business professionals need to learn new skills around design. It’s challenging and expensive as a startup to hire or crowd-source designs for every piece of content you produce.
I recommend trying new things to make your marketing stand out and checking out Lynda.com if you’re looking to improve technical skills. I don’t think it will disappoint.