Get your things together! This isn't all you need, look at "you will need" for everything you need :p
Glue paper on the box. This box was- how to say it- fattish? Anyway, felt won't stick to it, so I glued some paper on first.
(I just used normal glue, which can be used for everything)
When you finished glueing the paper on, look how big the pieces of felt have to be, and cut it.
Glue the felt on. If you have a moving part, the part where the box opens, have 2 pieces of felt, one above the line it moves, and one under it. If you don't cut it in 2, the felt will start to look ugly after a while.
Glue the rest of the glue on. You might want to use paperclips or hairclips to keep it in place as you wait. It doesn't take a long time to dry but it can always move if you don't watch it carefully :p
Start making the blue rim. It should be longer than the monster itself. I wanted to give my monster a mohawk first, but it didn't really work, so I just got some beads to sew on instead, which looked quite cute. I used some flexible iron thread, sewed on, at the end of the tail to keep it on.
Give him eyes! You can use either felt, a marker, or those moving eyes. I used the last one.
Glue the blue tail thing on.
That's how it looks from the sides. I cut off the remaining felt, don't worry x]
Give him teeth, and your monster is done! :D I use him to store little pieces of felt, might make another one for candy.