I've already put my National Guard Pay on my Federal tax form, now I'm in the Oklahoma State part, it says Military Pay Exclusion. do I enter my federal pay again here.

[DawnC]

Yes.  If your legal state of residence is OK, then go ahead and click on Start next to the Military Pay Exclusion to exclude your pay.    You should see the income reported on your federal return and you will enter the amount that should be excluded.  

Oklahoma exempts 100% of active duty military pay from state income tax for residents who serve in the U.S. Armed Forces. This includes Reserve and National Guard pay.