Soak them over night in a jug of ph adjusted water..test in the morning to find the ph of the rockwool cubes...the solution in the jug with the cubes in should read between pH 5.6 - pH 6.
Take your seeds now and place them on the cubes and with a knife tip excavate some fibres from the surface of the rockwool , gently and surgicaly bury the seed under the surface . Close it over with some fibres from the surrounding rockwool..The seed should be completely buried but only by a thin layer of rockwool strands.
Keep in a warm place and in a few days you will have seeds sprouting up out of the cube and ready to be moved to the lighted grow area.
Use a "dome" or ..a small plastic tub [like me]
read the instructions on the Super thrive and halve the concentration when germinating seeds
"Now go home and get your fuckin' shinebox!"