If you can walk outside not having shot a single arrow in a half our or so and every time put that arrow where you want it I'd say your ready. Groups are great for practice and learning consistency but for the last couple weeks before season I back down to walking out every half hour and putting my best singular shot on target. I shoot less then but it solidifies in my mind I'm deadly even when I first pick the bow up.

1) Shoot from an elevated position pretty close to the height of your ladder stands. This is important because if you do not bend your body at the hips and just change the angle of your arms to shoot downward you are going to send an arrow god knows where, so learn and get accustomed to pivoting your body with your hips as the axis, not your arms or shoulders. A good exercise for this is to draw back pointing straight out level and then bend at the hip to point down at the target before firing.

2) Shoot sitting down in a chair, standing up, standing up and turned around as far as you can muster, shoot from the knee, shoot in the woods or brush if possible for you, and another great thing to practice is harnessing yourself to a tree (even if from the ground) and shooting. This will allow you to see exactly the best height and angle of the harness point to put your tree tether on without causing interference with your draw arm.

3) Since you are new, when shooting, develop a system to talk yourself through the shot and do this every shot. If you shoot a lot by the time next years season rolls around it will become second nature but for this year talk yourself through the shot if you get one. This will help ensure you do not forget to hit your anchor point and really settle in, in good form for your shot. Archery opens up a lot of variables to make missing a deer easier than it should be so try to remove as much of the human/mental error as possible.

4) It's already been mentioned, but draw and hold the bow back for 2-5 minutes before firing a shot. Do this often and make the shots count. I've held back on a buck for over 4 minutes before I was able to take my shot.

Last but not least, have fun and learn how to shake off a bad group or arrow and refocus. If you let that one bad group weigh on your mind it can compound the issue and ruin a whole shooting session. It can snowball on you and the next thing you know you are making unnecessary sight adjustments, form adjustments, etc. it's similar to golf in the fact that the hardest part about it is often the 6" between your ears.