53 man rosters

i was just wondering how we get down to are 53 man roster do we do something like the nfl dose. were on this day we cut down to say from 80 to 70 them on this day we cut from 70 to 60 and then on the last time frame we cut down from 60 to 53 and then there is a sort time were we can pick up any free agents that are cut from other teams to a day that is set before the start of the season. and i know we ask about making the rosters bigger has any thing came out of that so we can keep more player on are rosters.