The only mods you can do are from transferring your save to the PC, and then either giving it to a modder (one that isn't me, as I have a lot of PC mods on my Skyrim PC, and don't want to uninstall them) or extracting the Savegame.dat from the 360 file.
Then rename that to Savegame.ess (you can change the Savegame part to anything, but the .dat HAS to be changed to .ess).
Then you put it into your Skyrim PC folder (My Documents > Games > Skyrim).
Then just load the game, be sure that the PC version is at the same update that your console version is, and the current version for both is 1.9, torrent sites call it Update 12 (how would I know that

).
Then you can start editing your save via console, and this is SOME of what you can do:
-Rename (setactorfullname; setcellfullname (if I remember correctly), must have the Creation Kit for custom names, create a new plugin and create a new MESSAGE using the name that you want to use, as renaming can only use MESSAGES for the name)
--NPC
--Cell
--Creature
-bring up ShowRaceMenu (showRaceMenu)
-Use typically unused items and spells (must have the CK, create a small plugin that allows access to those items, spell are a bit trickier, but still easy)
--My personal favorite spell is called Bloody Grip, and it is basically Vampiric Grip (for Vampire Lords), but using it while not transformed is more fun
--Personal favorite item to use is the Elder Scroll that Serana typically uses. It just takes up the arrow slot
-Spawn static objects (placeatme; setpos; setangle)
--Walls, houses, barrels, etc
---You can build almost anything, but you can't create new cells
----What people do instead is rename a cell that isn't used, spawn its entrance, use MarkForDelete on almost every object in that cell, and basically build from scratch some kind of amazing area
Then there are the other ones that get used like:
-addspell
-setlevel
-advlevel
-setav [attribute] [value]
-additem
-setscale
-disable
-setstage
You can also use the commands to fix any bug that you come across.