Brand new battery, any pointers?

I have a used laptop (IBM T20 Thinkpad) and the battery sucks unless I do very little (Word or Excel). I just bought a brand new battery, and before I put the battery in, I have a question. Do I need to do a burn in of sorts, or keep it out of the laptop when it's plugged in or what? I paid $50 so I don't want to be buying another every several months. Any help is appreciated. What I'm asking is could any of you please explain to me the initial charge process.

Just put the new battery in and let it charge up. Once it's fully charged, you're ready to roll. You can leave the battery in while using the computer on AC power with no problems.

Under normal use, batteries tend to last 1-2 years before needing to be replaced. Basically, a LiIon battery's capacity decreases as the battery goes through more and more charge/discharge cycles. The less you use the laptop on battery power, the longer it should last. If you don't use the battery much on laptop power, you could get lucky and have the battery last 2-3 years or more.

thanks skydog, i just didn't want to screw it up and maximize it's effectiveness.

Yeah, there's very little you need to do, or can do, to "condition" a battery. You can increase battery life by lowering the brightness of your LCD display, or undervolting your CPU. Pentium-M's undervolt very well, and you can usually squeeze another 20-45min of battery life out once you undervolt.