You need to wait til the female is at least 30-35 grams, just for her health before you put them together.

Here, I stole this off of Pangeareptile.com:

In order to induce breeding, temperatures should be kept between 75 and 80 during the day and dropping up to 5 degrees at night. The enclosure should be misted lightly once or twice a day particularly in the evening, however you should not soak the cage so much that it doesn't dry up in a few hours. Special attention should be paid to making sure the breeding crested geckos are getting plenty of high quality food. Gut loaded insects and supplemented baby foods are great. Make sure to dust the crickets and baby food with a good Calcium and Vitamin D3 powder at least 3 times per week. Check the calcium sacs of your breeders (located on the roof of the mouth) once per month to make sure they are not getting depleted.

An egg laying container should be used inside the cage for the females to dig in and lay their eggs. The container should be large enough to accomadate the female and allow her to dig down at least 3-4 inches. It is recommended that the egg laying medium be a 50-50 mix of moistened Peat Moss and Vermiculite. However straight Peat Moss works too. A piece of cork bark works well to conceal the container and make the female comfortable laying her eggs. You should check for eggs every morning while they are breeding and remove the eggs promptly so they do not dry up. Females will lay a new clutch of eggs every 25-35 days. The eggs should be placed in an airtight container with 2 inches of slightly moistened (3 parts water to 4 parts substrate-by weight) vermiculite, perlite, or a mixture of the two. I prefer to use Vermiculite. The top should be removed at least twice a week for ventilation and to check on the eggs. I keep the eggs at a constant 76 degrees and they hatch in about 60-70 days. Eggs have been hatched at a variety of temperatures ranging from 72 to 80 degrees. I would recommend incubating somewhere in between. Temperature dependant sex determination (whereby the sex of the offspring is determined by the temperature at which they are incubated) has not yet been proven with crested geckos.

Females can also retain sperm, so, even if you take her away from the male, she can still lay eggs for awhile after that (which it is recommended to let her have a little alone time every now and then ) Good luck!