Once you power up your machine for the first time, check the battery charge in the top right hand side of your menu bar. If it's not 100% I would let it charge up to 100%. If it doesn not reach 100% then I would calibrate it.
Apple recommends that you calibrate your battery at least once a month. Discharge the battery all the way, remove it from the machine for 4 hours, then replace the battery and let it charge all the way up.
The new baterries nowadays are not a prone to the "memory" issues of the old days. I would not be too concerned about conditioning your battery the day you get it. Maybe after a few weeks of normal use, I'd calibrate it. Mine, even though it's been plugged in over night might read 98% instead of 100%. At that point I calibrate it. Next time I charge it, it will read 100%. I don't calibrate it every month. I try to, but in reality, probably every 2-3 months.