Yea, I don't recommend locking the legs while doing overhead presses. That increases the pressure on the spine. I recommend using a slight bend in the knees to take some of the load.
I def agree, slight bend in knees. Also as Evo stated, you can give a slight push with your legs. Be sure your form is right on, it may take a few times to coordinate between pushing the weight up and driving with your legs at the same time.
i tried out doing the bb shoulder press the way u guys recommended .. i never knew what i could do before .. so basically i did 85lbs ..and towards the end it got tough .. i know i know .. the number pretty low .. i guess my spirit was broken after my bf assessment and then some criticism
another question .. when i do standing military presses .. ive been bending my kneees and giving myself the little push .. i was just wondering does that take away from the excerise ? and basically turning it into a push press ?