Things i should do before and after buying t-mobile cell phone on amazon?

[Wheatmaster]

i'm going to be buying the samsung e105 from amazon with the $250 MIR so i earn $20 in the end. What are things i should know, hidden fees/taxes, how do i activate the phone when it gets here, etc. Thanks.

 

[Ameesh]

if you buy the plan online it will come activated when it arrives