Zachary Thomas
Liking YTtalk
I use GIMP its a free Photoshop basically, takes getting used to but once you grasp the concept you're golden
Btw @Ninya, I think you need to fix your channel link, if you have less than 100 subs you will have to post your channel's link but in this case it is a like a code (like mine) so when you link your channel you need to click the button channel then post that code on your URL after youtube.com/channel/(Copy this only). Your link won't work otherwise if you just put your youtube channel name.If you want an easy way to create thumbnails use Picmonkey its free and easy to use or you can use Photoshop and I have a video no my channel on how to get it for free in like 2 minutes and the link is probably gonna get deleted sooner or later so download it and see if you like it
You really cant go wrong with Photoshop. I started by using Paint.net as an easy free method of making basic custom thumbnails. As I got more serious with it though I realized that I needed to really work on creating better looking thumbnails because having an enticing professional looking thumbnail is incredibly important. The thumbnail is like a book cover, you really need to put some effort into making it stand out. I highly recommend taking the time to learn some basic Photoshop skills. You can buy the elements version of Photoshop which is much cheaper than the full version and it will give you plenty of tools to create some nice thumbnails.
Good luck, I hope you find a good solution that works for you.