Take some sandpaper to smooth the edges!
Also use it for the inside of the little 'door', it has to be smooth, otherwise the blackboard is too rough.
Paint it, use some tape for the edges.
Let it dry. Paint another layer.

I used this sort of nail to secure the rose on the wooden board.

Search on cutoutandkeep for 'Magazine bowls. Use the 'How To' to make your own magazine bowl for crayons or your keys!
Or simpely use another bowl, but making one is always more fun.

I used the same 'How To' and a little bit of imagination to make a butterfly.

Use a (water)level when hanging the boxes. It is quite tricky, so have someone to help you with this.

I first drilled some holes in the boxes. That makes it easier to secure them to the wall.

IMPORTANT! It is a very good idea to make the collage on the floor first. In that way you can measure the distances between the boxes and make it look very neat!

I used all my perfumes to fill it up.

Ps. The little cushion is filled with lavender, it smells really nice when you squeeze it.

Have fun!