This is a canvas I made a few years ago to represent my life at that time.
1. Choose things to go onto your canvas and arange them.
2. Glue everything onto your canvas.
3. Make a mix of water and PVA glue (1:1) and cover everything in it, then in a layer of 1 ply toilet paper. (Note: you can just seperate the plys of the paper you have in your house). Use a brush covered in the PVA mixture to push the paper into all the little spot so that you can still see the details.
4. Repeat 2-3 times.
5. Give everything a coat of black paint. (possibly 2 depending on the coverage) After its dry, look at it from every angle to spot any hidden spots that didnt get painted.
6. get a sponge or a old rag (not tissues because they stick) and dab it in silver paint. Dab it on a spare piece of paper/plastic until theres almost none, then dab it onto your canvas. Keep going until every raised piece is covered, or your happy with it. (Note: having next to none on the sponge makes all the raised details visible on the canvas.)
I used a variaty of things on mine that I thoguht reflected me at the time. In the classroom I've set this up as an art activity to show communication on a piece of card rather then a cavas. This could be used for almost anything.