You might want to check your local regs to see if 40 lbs is legal to start with. Secondly draw weight alone is not the only factor. What is your draw length and what type of bow is it?

Truthfully it doesn't take much to kill a deer if you have a well tuned set up and skill. And you may have to do some tracking as well. Don't expect a 40 lb bow to get a complete pass thru and drop the deer 10 yards from where you shot it. That is rather unrealistic goal.

Set up like you would with a traditional rig. Stay away from light arrows and use a 2 blade cut on contact head. And make sure the blades are WICKED sharp. Also make sure the bow is tuned the best it can be and that the arrows are as close to the correct spine as you can get them.

Then practice, practice, and practice some more. If you are going to shoot from a stand, practice from one.

Practice estimating range, or better yet range off a perimiter around your stand before hand. That way you know when the deer are within 20 yards, you won't have to guess. That rig will not allow for any errors in range estimation.

Shot placement is critical! Learn deer anotomy and where to put the arrow, then pracitce doing it. Also try to learn as much about deer body language as you can. Try to shoot them when they are relaxed and broad side. Always think about where the arrow will go, aim for an exit wound, even if you don't think you will get it. And don't take risky shots with that set up! They just won't work. If you don't feel 100 percent about the shot, don't drop the string. You will thank us later for that advice. It's hard to let them walk away, but it's harder to stick an arrow in one and not find it. Unless you have no compassion at all that is.

Keep your shots inside of 20 yards, and try not to make really close shots either. You know like where you are aiming right down on top of the deer. These are very hard to make and have a fairly low percentage of success in most cases. Practice them though if you get the chance.

Bow hunting is so much more than shooting a bow. Archery is only one part of it. That is an art and accomplished skill on it's own. Then you have to hone your hunting skills on top of it. Do some wind sprints in your yard until your heart is pumping hard and you are sweating and shaking. Then draw your bow and hold it for say 30 seconds, then try and shoot. It's not easy.

Of course you have to be good enough a hunter to get them within 20 yards to begin with. That's my biggest problem. I shoot pretty well, I'm just not that good of a hunter yet. I can't shoot what doesn't come into range or presents me with the right shot opertunity.

Also most bow hunters have slightly higher ethics then gun only hunters. Not always, but for the most part this is true. Expect to be held to a higher set of standards. Going out and just flinging arrows at deer will not be tolerated in most cases. Do the homework and practice. And don't be afraid to ask questions, no matter how stupid they are. We have some excellent hunters and archers here. They are here to share what they know and help others. Don't be afraid to take advantage of it.

Let us know what kind of bow you have and what your draw length is. This will give us a better idea. We may be able to help with your set up as well if you need it.

Good luck, and welcome to the forums.
Paul