I have read some threads about shooting over the back while your in the stand. Should I pick a spot a little lower on the deer? I'm 18 feet up.

if your shooting 18 feet up then you would want to pick a spot on the high to mid part of the lungs that way your arrow will hit there then you will center the back lung and have a dead deer not to far away, of course you will have to take into account the angle of the deer...Curtis

If they are nervous-aim low or better yet dont shoot. there is something about shooting down or up that will make you strike hi or lo but with trad gear??

Just practice from a stand, be sure your sight (eye) is tuned in!

Seriously-just practice,

J

Would it help if I lower my stand 4-5 ft?

Reducing your stand 4-5 feet will help you get a better angle into the deer's boiler room.  I don't have a single bow stand set over 12' to the platform.  And I too have shot over the back of one this year.  As already said you'll need to practice shooting from the height you hunting from.

Madness 522 Any problems with the deer vcatching your movement when you are that low?

frassetor, shooting over the back of a deer from a tree stand, is most likely caused by not bending at the waist to shoot down, and just lowering your bow arm instead. It really throws things off.

You'll need to move slow all the time not just when you have a deer near.  I usually keep my bow upright with the tip on my boot to minimize movement.  One other thing you can try is hang your stand above the first couple limbs on the tree.  For some reason deer all but stop looking up a tree when they see the first limb.