I (C) saw someone post an example of this on tumblr, but it looked super complicated. I set out on a easier way so that those of us who are photoshop impaired could have some fun too! (Warning: You're going to want to make five of these!)
Step 1: Select a cute desktop! I've used Lilly as well as other fun patterns! We'll be using a navy chevron one! Make sure it's large enough, or else the image will get distorted.
Step 2: Upload it to Picnik. (I'm going to be so sad when Picnik shuts down in April!!)
Step 3: Go to the stickers section, and select a shape (I like circles and rectangles the best.) Change color as you wish.
Step 4: Add desired initial(s) or name! It can be a little tricky to size and color them evenly, but it's well worth it!
Save and enjoy!! Now you can make everyone jealous of your darling wallpaper! Have a great weekend!