You draw, then press the trigger on the release. The arrow flys just under the bucks belly or harmlessly over its back. This is a scenerio that happens to every bow hunter eventually. But there are things that you can do to limit this to being the exception rather than the rule. Hunting with a properly tuned bow is one of those things!
Getting your bow ready for bow season should be more than pulling it out of the closet and drawing it back to see if everything feels OK! When you venture into the woods you need to know your equipment will perform. Gaining that knowledge should start before you shoot your first arrow.
If you have access to a bow press you should inspect the Cam and shafts before doing anything else. Plastic bushings and shims wear over time so before the season opens you should check for nicks and worn areas. If any damage is found replace. Also check the cam(s) for excess lateral movement when on the axle shaft.
Check for nicks in the cam itself where the string is in contact with the cam. A nicked cam can damage your string, potentially causing injury. So make sure you check the cam for damage. The nicks can easily be fixed with a small file or even sand paper. Clean out all excess wax that has built up in the string grooves. Don't be tempted to use an oil as lubricant. Oil will only attract and hold grim. Use any of the graphite based ones. Put a small amount on the axle before you put your bow back together.
After putting your bow back together, check to see that your bows cams are in tune. This illustrates one of the advantages of single cam bows. Since single cam bows only have one cam, it is not possible for the cams to get out of tune. If one of your cams is lagging slightly you bow will not shoot tight groups. The way to check this is to slowly pull the bow back and have someone watch to make sure both cams roll over at the same time. Often the lower cam is the first to cause problems. This is because the lower cam takes more abuse. Not from shooting but from handling. Most people lower their bows to the ground with a string; therefore the lower cam is subject to getting damage much more easily than the top cam. Also this often cause more dirt and grim on the lower cam which can also cause it to loose its tune. So if your bows cams are out of tune visually inspect the cams for nicks and dirt.
Now that your bow limbs and cams are OK next check the riser and attachments. Make sure that all screws and nuts are tights. If you are using a prong type arrow rest that has a protective coating on the prongs to silence the arrow, you can remove all the shrink tubing from last year. Use fine sand paper and lightly sand the steel prongs. If you shoot carbon shafts you can very lightly sand your arrows as well to remove any nicks or imperfections in the shafts. Clean all moving parts of the rest with alcohol and lubricate with a graphite type lubricant where applicable.
Your sight should be checked to make sure that there are no loose parts that will rattle or come loose. You should check it over for cracks in the plastic or broken pins. The fiber optic tips common on todays pins are subject to getting cracked or even coming loose. Now is the time to replace any defective pins.
There is not much to cable guard rods and the small plastic slides, you need to check to make sure that it moves smoothly and is free of dust and dirt. If the plastic part is worn now is a good time to replace it. You might also want to consider upgrading to the newer Teflon slides. They wear much more slowly and travel more smoothly on the rod. If there are any nicks or scratches you can sand the rod as well. I would stay away from the roller type slides. This is a part where simpler is better. Rollers may work well, but the way I look at it the rollers just have more moving parts. So that is something else that can break or go wrong.
Next take a look at the string. First look at its serving. This is the wrap that goes around the string where the arrow is nocked. Is it coming untied? Is it worn excessively where the arrow nock goes. Look for fraying ends. If there is a problem with the server, you can replace it without also replacing the string. Also look for cuts in strands of the main string. The cables should be inspected. The new strings on the market will last longer than the old strings but they don't last forever. String stretch on a two-cam bow cause the cams to be out of time. This will cause erratic arrow flight. You can add a twist to the string to compensate for the stretch.
Once you have made a complete checked of your equipment your job of tuning will be much easier. If you cams are out of tune you should bottom out both limbs and then turn out the limb bolt in equal amounts. This will give you equal tiller setting most bows are set up from the factory to shoot at the same setting. If you have replaced your string or server you will need to make sure that you arrow is roughly centered with the rest and that the sight pin is lined up over top of your arrow and that the arrow is at 90 degree angle to the rest. You are now ready to paper fling a few arrows and make sight pin adjustments if needed.
With a properly tuned bow you will be a more confident shot and that will make you a better hunter.