Characters that change size regularly.

I am not a DM, I'm just a player trying to play a game of Pathfinder as a "Shifter" with a relatively new DM.  My character can change forms depending on what animal shape I take. For example, if I turn into a bear I become size = Large, and it changes my stats accordingly when I'm done I change back to a Medium sized. I'm trying to figure out how to quickly go back and forth between the forms without having to manually input my stats, and attacks each time.  Is there a good way to put this information in and alternate several forms? I've tried using macros/spells/etc but...I haven't figured it out yet.  Any help would be appreciated.  Using this: /w gm &{template:default} {{name=Dire Bear Major Form}} {{Size=Large}} {{Speed=40}} {{Vision=Low Light Vision}} {{Scent=30}} {{ClawAttacks=1d20 + [BAB]}} {{Damage=1d6 + [strength_mod]}} {{Duration=5 min}} It will print all the information for this animal form to the GM but it doesn't change the stats, and this is what I've been doing so far.

Without the API, your choices are limited. The easiest way is to pull your character token off to the side, and have the DM place a Dire Bear on the table from the Compendium (or from one created for the game, if Dire Bear is not in the PF Compendium. They should then give you control. You can move the bear around the table. If you need a function supplied by the bear stats, use the bear token. If you need to use your own, use your token. Alternatively, you can use a solution that requires more setup: Create a special character sheet for each of your most common forms. When the time comes to shift, place that one on the map. I don't know enough about PF shifters, or the sheet to go into more detail, but hopefully that will help you with some starting ideas.

Sounds like a good start.  Thanks.