what are the bonuses for being size large? would being size large add levels to your character?
http://paizo.com/pathfinderRPG/prd/monsters/monsterAdvancement.html This gives the general bonuses for changing the creature to any other size. These bonuses are to be ignored if you are becoming large by a spell or starting with a large race, instead referring to the spell or knowing that the adjustments are already taken into account in the race. Large (tall) also gives a 10ft space and 10ft reach. Usually, the size increase is taken into account with the spell or race that allows you to be large, and the only 3.5 guideline is that large gave +1 CR, and that by Pathfinder's using Monsters as PCs, it would act as a +1 LA only if you got large by a method other than a preset race, spell, or item. I hope this helps. If you give how you are getting large, it would make things easier.
Being large doesn't add any levels to your character. A lvl 10 Fighter with permanent Enlarge Person is the same as a lvl 10 fighter who spent the gold on a +1 sword.
Being large doesn't add any levels to your character. A lvl 10 Fighter with permanent Enlarge Person is the same as a lvl 10 fighter who spent the gold on a +1 sword.
This is one of the few ways to increase size that doesn't require you to invest a level some way or another. In theory even the gold spent requires a "level up" as you wouldn't have that amount of gold available if you weren't out adventuring.
Most ways of attaining large size usually require some sort of "level investment", either through a template (and associated ECL adjustment), advancement (adding hit dice adds levels and most creatures that are large have multiple HD and/or level adjustments) or through PrC classes (which require you to attain a level to gain the attributes).
Regardless, Kamai covered most of the bases and if you could explain what you are doing/how you are attempting to increase size it would allow for people to give you a more specific answer.