You can see in the above picture the beveled edge on the background itself.

Antonio is such a special and wonderful son.  We all love him dearly and cater to him a bit, his needs, wants and desires.  He is just so precious and caring to us all and he rarely asks for anything.  So when he does, we try to make it happen for him.  Also...as our children are given money for holidays and birthdays, they choose something they really, really want and save for it.  But Antonio is so limited in what he can do or spend his money on, that when he chooses an animal, we also try to make it happen for him.  He does a lot of sitting.  He loves to sit and watch his animals, especially reptiles. (but not snakes he is quick to say!)
So when he asked for a lizard, to spend his birthday/holiday money on, I started to do some research.  smoke detector Yes, I am the one to care for his animals so my search was for the easiest to care for lizard out there.  Time and time again leopard geckos kept coming up.  So I told him if he wanted a lizard how about a leopard gecko as I could easily care for it and they were interesting and came in very nice colors.  smoke detector He got very excited about it and so, as a project together, smoke detector we have spent hours on line researching and watching videos about leopard geckos.  We have been slowly buying all the things to set up a very nice gecko cage.  It has been slow going, as part of the fun in getting the pet is the preparation and learning.  He has bought what was needed as we learned about it all.  He then got very excited about the nice backgrounds available that people were making.  So since I am a project person, I told him I would do the background for him as he watched.  He has enjoyed it all very much.  I will show you what we have done.  I must put a disclaimer here as anything you build for any pet, do research and use all pet safe, tried and true methods so as not to kill your animal.  In other words, if you are making this for a reptile terrarium, make it at your own risk. First, I went to Home Depot and bought these square smoke detector insulation boards. 
Then I cut a piece to fit the back of his tank.  I cut it about a half an inch shorter top and sides, because smoke detector I knew I was going to use tile for the flooring and that would raise it up some.  The large sheets were a lot more expensive than these small squares.  I did not want to pay the price of the huge sheets of board and these were a bit short for his tank so I did glue two pieces together to make it long enough, so there is a seam in our background.  Antonio and I am sure the gecko will not care.  I was trying to save money and do this as inexpensively as possible. Then I cut two pieces (the same shape) in the basic shape I wanted (like a rock) and glued them on top of each other with Lock-tite and let them dry/cure for 24 hours.  I made four of these.
Once I had the rocks shaped, I took the background and just randomly cut the front edge all the way around to make it beveled. I wanted the rocks to be placed on the background so that the lizard could climb up from one to another like stairs.  So I started gluing them on in order from the bottom in the pattern I wanted.  William made me little lego scaffolding the right height to hold the rocks on the background straight till they dried/cured.
You can see in the above picture the beveled edge on the background itself.  I also made a freestanding smoke detector rock and carved a little cave inside smoke detector for under the right side in the space at the bottom smoke detector as leopard geckos like to hide.  I understand there is many ways to go forward from here.  Some people texturize the whole thing with a hot torch or heat gun.  Some people use several thin layers of watered down grout to make it almost rock like.  Doing that fills in any faults and cracks.  I went with the spray paint approach.  According to those who have done this before as long as you use water clean up/based spray paint you are ok.  So I then took Rust-o-leum home accents "stone" paint and spray painted each piece with several coats.  Then went over the whole thing with a thick layer of water based polycrylic.  smoke detector (again use at your own risk)  Some people sprinkled sand onto the last coat of polycrylic for texture and to take some of the shine off it.  But I figure smoke detector the shinier, the easier to clean. 
So smoke detector here it is all done with the tile down and the background curing for a week or so. Antonio is very excited and has really enjoyed this project.  I have enjoyed spending the quality time with him working on this for him, with him supervising, telling me suggestions and asking questions.  We have learned a lot. May everyone be settling into a good routine after the holidays and enjoying this brand new year.
Hebrews 6:10  For God is not unrighteous to forget your work and labour of love, which ye have shewed towa