Good advice from elknut. He has lots of experience and knows what he is talking about.

One additional caution for a first timer is to not get that draw weight poundage up too high on your bow. In the field you may not have a perfect setup where you can get a straight pull on your bow, you may be turned or on one knee or some other less than perfect situation.
Also you will be surprised to find that when you see that bull and he comes in screaming at you at 40 yards your heart will pound in your chest and you will get weak in the knees and that 80lb bow that was so easy to pull at the range may suddenly feel like 150lbs.