A collection of handy resources that have been useful to us, and will be useful to you.
I used Photoshop for over a decade, but for the last few years I've switched to Affinity Photo. I love using it and cost the price of one month of Create Cloud, which I gladly cancelled.
Free web-based alternative:
If you're looking for a banner for a channel other than gaming related, check out my 10 customizable banners in different genres.
Channel art size information, which part of the banner displays on each type of device.