I am pretty new to reloading. What do you do, as far as preperation goes, when it comes to new factory brass. Does it need to be sized and trimmed? What do you guys do??? I just bought some Winchester .220 swift brass and would like to know.

I've found that most if not all the new Win and Rem brass I've purchased has required a trip through the sizer die, as the necks have been dinged up. I'd check the OAL after sizing to see if trimming is required. If not, prime, charge and seat bullets, staying within published data, and you're on your way!

With brand new brass I start by a short tumbling session to get any manufacturing lube etc off, inspect all the primer pockets and flash holes and do any cleanup needed, then chamfer the mouth, full-length size the brass, then measure it and trim if necessary; followed by another short tumble to remove case neck mica and case lube. I have always read that the first time a case is sized is when it will "grow" the most, so I don;t trim until after that first sizing is done.

Hoghead, What kind of shooting will you be doing? Hunting, plinking or serious target shooting?
My new hunting ammo brass is bought in lots and gets:
Flasholes deburred.
Trim to proper length and debur case mouth.
Full length resized first time, neck sized after that
A very light clean up turning of the case necks.
Prime and load.

Target ammo gets the works.

"The Ultimate inn Rifle Accuracy" by Glenn Newick describes in detail the process for accurate benchrest shooting ammo brass preparation.
I'm sure others in here will offer some great advice on brass prep.
Hope this helps and good shooting.
*Nut*

Run it all through a full length sizer, then measure them. Trim them all to the length of the shortest case....

Just another note:
I have found that winchester brass is in a lot better shape than remington when it arrives, therefore less work before there ready to go.