Hiya marky and congratulations on your first sowing! I am no way an expert, but, as I am the first to reply, I will tell you what I do (don't tell me off everyone if I am doing things wrong). I use multi purpose compost, fill my pots or seed trays, and sow. ;D I always read the seed packet and if the seed packet says cover with plastic, I do, if it says don't deprive light, then I don't cover the seeds with compost, just surface sow, other than that, I lightly sprinkle the seeds over the compost, lightly cover, water with fine rosed watering can, label (if I remember :-\) and leave in my greenhouse. If a frosty night is forecast, my little heater kicks in. My cabbages lettuce and leeks were up in a matter of days. I'm sure yours will be to.