First of all, make a shape in you head, not so complicated though, and with the sticky tape copy the shape to your wall.
After that, think of what color will what be. (if you are not sure, color the paper with your ideas)
Prepare your paint. The process depends on how long the paint needs to dry, and get ready to paint!
Now my favorite part! Color the wall as you wish!
Wait for the paint to dry, and then slowly take the sticky tape of.
And that's it! Now, I will start to add some pictures and stuff that I like to personalize my wall, below is another picture of an another wall that I painted as well!
My other wall, paint and decorated :)