The best thing about Canva is that it's FREE. There is an upgrade option available, but I couldn't find anywhere on the site what the upgrades were.
It's an easy tool to create simple visual designs.
Canva offers a lot of great templates. This is helpful when you're unsure about the size you need.
I've chosen the Facebook page template. Now you know exactly the space your profile picture will take up. The menu provides a lot of background options from free to 1.00.
The Text menu gives you font and color options along with labels.
You can upload your own images. Change the font and color, move images around.
And Voila! This is really simplistic, but you get the idea.
Canva doesn't have the design palette of Picmonkey, but at least it does save your work so you can make changes later if you want to. I often use the two together.
Have fun with Canva!