Hi there!
The top 2-3 inches of your growing medium/soil should be dry before you water. When you water, really saturate the soil. In general, you wantto keep the light as close as possible without burning the plants. Run a fan, so that it blows air between the tops of your plants and your light.

Start with your light 1-2 feet from the tops of your plants and move it closer by 1 inch everyday. Do the hand test... put your hand at the same level as the tops of your plants. If your hand can handle the heat, so can theplants..

good luck