My son has a lot of resistance to go to sleep (as many kids) so what I'm looking for is a not very powerful light that create a shape familiar and comfortable (yes it's true the T-Rex is not so "comfortable" but my son is crazy for dinosaurs :))

You can choose any kind of shape you prefer as the method is very simple. I hope you enjoy this build together with you kids

Step 1: Material Needed

This project is very simple and cheap as you can reuse any kind of scrap of wood or paper you have

Anyway this is my list of materials

A piece of plywood of around 20x20 cm (choose the measure that fit your model)
and no more than 3-4 mm of thickness
A piece of plywood of around 10*20*1.5 cm for the base
A little led bulb (prefer led technology as the bulb remain cold without possible dangerous situation)
Electric wire, scissors, jigsaw etc.

Step 2: Transfer the Model Into the Plywood

There are two ways to transfer the shape of your model into the plywood, all of them are good it only up to you decide which one do you prefer.

The first is to print your model and literally attach with glue on your plywood

PRO

Very fast

CONS

Sometimes the paper goes away during the sawing
You need to remove a lot of glue later

The second (that I prefer) is to print your model and with a couple of scissors cut around the paper in order to obtain a clean shape. Then put your shape on the plywood and with the help of a pencil trace the contour directly on the plywood.

PRO

Very precise and clean

CONS

A little bit of more effort in order to prepare

For the model you can use the one I've processed or you can choose the shape you prefer

Step 3: Sawing

Using a jigsaw follow the path you have traced with the pencil.

If you are not a jigsaw enthusiast is matter of patience, patience and a little bit of patience

After that take your second piece of plywood (the one for the base) and using a router or a chisel or any kind of tool prepare a slot for your shape. If you don't want to prepare a slot you can use a little piece of wood in order to attach the shape using only glue.