yes, thats the best way to do it b 4 you get to know your soil. im not familiar with mother earth terra, but from what i have read, its good for seed to plant, well about 4 weeks growth if its like our (uk) potting compost. but i think its better than that and will last you longer. just water untill the first round leaves turn yellow and feed with a good organic fertilizer. im experimenting with intence nutrients on a plant or two this year.
i usualu use a good potting compost with an organic soil improver mixed in and some soil amendments like fish blood n bone meal/pellets, chichen manure pellets and some seaweed meal.
you should look into alfalfa meal to use in your grow. look into organic teas to feed the plants with also.
im useing bone meal rock phosphate and im making my own potassium phosphate from scratch, whjich involves maling my own phosphoric acid from scratch and useing natural chemicals from scratch, facinating stuff, but beyond the reach of most first timers.
byut theres great info on super soils you maywant to look into for your next grow or the one after. i sugest you KISS keep it simple stupid (dont take offence, its just a saying). the simpler the better
so start with a good organic fertilizer, just use the search engine for ideas.
watch n read your plants, like waiting for those first leaves that open when you sow a seed in some seed and potting compost or mother earth terra (from what i have read. use some pearlite with it, say 20 % with the soil, this keeps the soil open which means its got air and water holding properties.
then after the seed has popped its head out of the soil, use a spray bottle to water it for the first few days, then use a small shot glass of water or two to water it/them for a few days. or you can put your pot of soil in a saucer or water tray and put water in the bottom of it, dont leave loads of water in it, just enough to allow the soil to suck it up, you can tell when this happens, as the surface of the soil will be moist to the touch and you can get a good visual of the wetness of the soil. a lot of new growers over water or under water there seeds and seedlings. you can avoid this if you just put enough water in the saucer or tray as ui have explained.
put your seed into a 6" tall plant pot to start with or a solo cup with holes in the bottom and keep it moist with a spray bottle. most soiles will come moist . untill it pops its head up out of the soil. this is when you put it under the light, not so close that it cooks it, but keep the light within the recomended distance from the light or you will burn it.
to make things simpler, talk to us about your set up, grow space size, tent or designated area of the grow space.
light your going to use
or if not sure of what to use, tell us your budget and whare you have to grow in.
sorry if this is overload info for your first time and just tell us your grow space and your cash that you have too spend and we can help from there