Don't take this the wrong way, but starting with baby tears may not be your best bet... they are notoriously hard to grow even for some of the more experienced members...
But if you want to try it out... start with a good base substrate, i'm going to say ADA Amazonia II soil, setup the tank without water... as in how you would like the hard scape to look...
Then place the baby tears apart from each other so its together in small clutches, and add just a enough water to keep the soil wet, but not completely cover the baby tears...
Then you'll want to cover the top of the tank with something like cling wrap so keep the moisture in the tank very high, add good lighting and then wait for your plants to fill in the space... once its filled in, then you can go ahead and fill the tank as normal and hope your plants don't suffer any melting...
As a side note... once you start really getting into using Co2, ferts and stuff like that is when your really going to have to monitor your water all the more to make sure everything is balanced in the tank, coz too much or little of one thing can cause some major algae out-breaks...
anyway, good luck with your project...