They are pretty easy to take care for; they like it humid but with good ventilation so in other words let it dry out a bit too around 50% for awhile then peak at 80% a couple times a day. Temperatures should be kept at 70 with a low 80 so just keep the cool side at 70 and the basking area at 80.
Babies may only take lizards/frogs and require scenting to get them switch over and if you have access to pinkies that would be even better. Adults you can feed rodents with no problem without scenting.
They are awesome to watch eat but be sure not to over feed. Feeding them bi-weekly or once a month wont hurt them if you give them appropriately sized meals. The key is to make sure they are not fat but healthy. Two major problems in the hobby is people think because the snake is fat means it heals you not true causing over weight means health issues.
If you are having humidity problems you can use a humidifier and set next to your enclosure or just mist several times a day.
For substrate use sphagnum moss and just add water to the moss and spray several times a day this will increase the humidity in the tank.
The enclosure should only be a 40 gallon tank any bigger and you have too much problems with keeping the humidity at the level that is good for you boa. You can use a reptile bulb for the basking side not to exceed 80 degrees. Put a hiding box on the cooling side a couple of rocks for the shedding process.