1) Remove the seat post from the bike using the quick release mechanism.
2) Significantly loosen the binder bolt--to the point that the pieces can rattle when you give a little shake. (You will see very small grooves machined across the width of the clamping mechanism. Hidden from your view are complementary grooves in the upper cradle of the post itself. These pairs of grooves engage each other to prevent movement once the angle is set.)
3) With the parts loose, you should now be able to change the seat angle...Rotate it in the direction you want to get it close, and tighten the binder bolt finger tight. Range of movement is limited by a slot in the lower clamp plate. Do not enlarge this, as it may weaken the clamping mechanism and lead to failure.
4) Reinsert the post in the bike at the height you want.
5) Now, with a closed fist, tap the seat angle to the position you want--level with the ground is the standard-- put a bubble level on the seat to get this right if you want to be certain.
6)You can also move the seat forward or rearward as you like.
7)Tighten the binder bold VERY tight to lock the grooves and seat rails in place. (But not so tight the bolt breaks).
8) Test ride the bike a bit to make sure nothing in the seat mechanism moves and retighten as needed.
Check out the video below, which shows you how to handle this procedure