I need a good way to get abs, it hurts my back and tail bone when i do sit ups o!

I need a good way to get abs, it hurts my back and tail bone when i do sit ups or crunches. what should i do?

Any ideas i have a longer tail bone i think. and im tall for my age.

you need to strengthen your core muscles as this is the cause of your lower back pain. when the muscles of the inner/outer thigh and hips are weak muscles of the lower back are called upon to perform the movement of shortening the abdominals.