Eggs should be incubated at 82-85 degrees (We incubate at 84 with good results).
There is no need to buy an incubator, you can build one! I would set it up now so that it is stable for when your female lays her eggs.
Ingredients:
1 plastic cooler
1 submersible aquarium heater
3-4 plastic "shoe-boxes" with covers
1 bag of perlite
a few bricks
a nail and a lighter
a marker
thermometer (digital ones with probes are the best)
Ok, here goes. Put the bricks in the bottom of the cooler. Fill the cooler up until the water is at the level of the bricks. Fill the shoe-boxes up 1/2 way with moistened perlite. Use the nail and the lighter to put lots of holes in the plastic lid. I'd put as many of the shoeboxes, with the perlite, in the cooler as you can fit. She will most likely lay more than one clutch. Use the marker to label the boxes (we use numbers) so you can tell them apart, keep a record.
Put the aquarium heater in the water (make sure it is completely submerged). Set it to where you think it should be and let it heat up the water. Place the thermometer in one of the boxes and wait. In 6 hours come back and read the thermometer. Keep making adjustments until you get the right temp. Keep the incubator in a cool room where the temp doesn't change too much.
That should do it! This is how we incubate all of our eggs! No fancy incubator for us!! It works great! The water in the bottom keeps it nice and humid. If it gets too wet in there you can prop the top open with something to let more air in. We tend to keep ours closed all the time.
Let me know if you have questions!
Good luck with the babies!!! 
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Kelly Affonce
DeKeaff Exotics
www.dekeaffexotics.com
AIM: DekeaffGrrl