Okay, bark chips aren't a bad choice. You probably won't have problems with it. But be advised that some bark chips can cause respiratory problems. There are better choices out there. If you want to use bark, use orchid bark.
Cedar shavings
Not only do cedar shavings cause respiratory problems and secrete irritating oils, they just look weird in a reptile enclosure.
Sand
This means any kind of sand, whether it says it's made for reptiles or not. Some examples are play sand, Calci-Sand, and Repti-Sand. They're all potentially fatal if ingested--not because they are toxic, but because they cause intestinal blockages.
Aquarium Gravel / Pebbles
Has the potential to grow mold. Who wants a mold factory in their room? Although your Anole shouldn't spend much time on the floor, pebbles can be abrasive as well.
Soil containing perlite
What in the world is perlite? It's just the fancy term for those white "balls" in potting soil. Perlite is used for aeration and moisture retention. It is made from rock, and it isn't digestable. Just to be on the safe side, avoid using soil containing perlite.
Soil containing pesticides or weed killer
Kinda self-explanatory. In the hypothetical, yet highly probable, situation of an Anole ingesting the substrate, pesticides and weed killer show no favorites. It'll kill your pet too.
Grass clippings
May contain pesticides and weed killer, and the dust from grass clippings can potentially cause respiratory problems.
Printed newspaper
The ink may cause skin irritation.
Bed-A-Beast / Forest Bed / Eco Earth / Coco Bedding
My personal favorite, this bedding comes compressed in a package about the size of a brick, and expands to nine liters once it is soaked in water. It is relatively inexpensive for a generous amount and is sold in almost all the pet stores now. However, it does take some work on the user's part to convert it to a usable state.
[ + ] Natural look. Keeps humidity relatively well. Usually inexpensive.
[ - ] Like I said this bedding comes compressed in a package about the size of a brick, and must be soaked in water before you're able to use it. That's pretty cool. But if you're impatient like me, soaking the brick of bedding and then waiting for it to dry can become tiresome. I put it in the oven to dry it.
[ u ] Soak the brick in water for 30 minutes or until fully expanded. Then let dry. If you're impatient, you can bake it in the oven to dry it faster. Put it in the oven at 250°F and check on it every couple of minutes. Stay in the kitchen and don't forget about it....just in case, well, you know. Firefighter: "What were you cooking?" You: "Umm...some....uhh...don't you have some more fires to put out?" Anyway, once it's dry or slightly moist and cooled off (if you put it in the oven), place a 2-4 inch thick layer of the bedding in the enclosure. The thickness just depends on how you like it. You can put just enough to cover the bottom, or build mounds out of it. Two inches is thick enough to hold some moisture.
Sterilized Potting Soil
[ + ] Natural look. Holds humidity very well. You can grow plants in it.
[ - ] Can become too damp if you aren't careful. Also remember what I said earlier about perlite, pesticides, and weed killers.
[ u ] To sterilize the soil, put enough for the enclosure in a baking pan, and bake in the oven for about 8-10 minutes at 250°F. This kills any parasites or insects. Place a layer on the bottom of the enclosure. Again, the thickness is your decision. Two inches is a starting point. It will need to be thicker if you plan to put plants in it.
Sterilized Compost
[ + ] Non-clumping. Very absorbent. Digestible.
[ - ] May become too damp.
[ u ] Run finished compost through a 1/4" hardware cloth sieve and then cook it in the microwave for about 15 minutes on high heat (depending on the amount).
Paper Towels
[ + ] Very easy clean-up. Cheap. Crickets and mealworms can't hide in it.
[ - ] No advantage when it comes to humidity. Not much to look at.
Terrarium Carpet
Just a green carpet. They sell it at the pet store, but you may be able to find it cheaper at a hardware store.
[ + ] Easy to use.
[ - ] Insects may be able to hide under it. Will become soiled and need replacing.
[ u ] Cut it to the correct size and put it in the bottom of the enclosure. You may want to tape it down to keep insects or adventurous Anoles from crawling under it.
