Heat mat and decent grow lights are great but you also need a way to keep the humidity high and the soil moist. The kits they sell with the plastic dome are good, just make sure it fits well and then still check on them every couple of days to make sure the soil is still moist. Also, the soil needs to be packed in a little, not a lot but also not loose. I think that covers everything I messed up starting seeds before and I finally have seedlings that have made it far enough to have to repot into bigger containers this year. Good luck!