GordonRS...
I tried to upload a post to you, but due to the length, the forum [???] would not accept it...that is why I offered to PM...
I will try again...
1. Your Shotgun...is perfectly acceptable with a 20" barrel...ammo companies design their sabot slugs around that length... assuming it is a rifled barrel, purchase a box of several types of sabot slugs...you have to find out what your gun likes (my shotgun really likes the Hornady SSTs)...bore sight your shotgun to get it on paper, then with specific aiming points fire 3-5 rounds of each type to find the most precise ammo (50 yards is far enough away for this)...after you decide what to shoot, buy several boxes and sight the gun in at 75-100 yards.
2. Your Scope...shotgun recoil is rough on a scope so the general rule that you get what you pay for goes double here...invest in a scope made for shotguns (preferably with a bullet drop compensating reticle)...Bass Pro/Cabela is a good place to check out a lot of different scopes at one time...I like the Nikon series...be sure to get a quality (steel) set of scope rings...
3. Your Equipment...get a climbing stand that you can carry in/out of the woods...watch the weight...many of these stands are really too heavy / but make sure the stand will support you...try to find deals in the off-season or on Ebay, etc... go for under 20#...when at your tree, try for a height of about 20 feet (use a 20 feet pull rope and go up until it tightens (you will feel it), but stay with background cover, even if it is a bit lower...make sure you have a good safety harness and use it... Place your stand on the NORTH side of the tree when feasible...
Buy a Windicator bottle ($4 at Walmart)...little white bottle that puffs out talc to indicate the wind direction...when used up, you can refill it with corn starch...I use mine to death...remember you want to set up so that any wind is blowing from where you expect the deer to be (trail) to your stand... Don't fight the wind--you will loose!
4. Scouting...most DNRs have maps of public land (and this CAN be some very good hunting)...the best time to seriously scout (other than while hunting) is AFTER the season closes (snow on the ground for a couple of days can really point out the trails) when you can easily see the rubs/rub lines and/or scrapes...record locations of trails and other sign with latitude/longitude (a GPS is great here, but a smartphone will do this too)...
USE Google Earth...you can create flags by inputting the lat/long with a description...after a couple of years, you can really start picking up on deer movement patterns...
5. Deer Patterns...deer have the same basic requirements as humans...food, water, shelter, safety and reproduction...unless you are hunting a really dry area, avoid the water deal...locate food sources (but they will change throughout the season) and bedding areas (generally any area that you don't want to go into will hold deer)...follow the trail between the two...look for geographic features that funnel deer into a bottleneck (creeks with steep banks can do this...find the crossing)...preferably with two or three trails intersecting and deer sign (some big rubs, etc) nearby...pick out a tree or two or three based on the prevailing wind conditions (generally out of the west)...
6. RUT...prepare to stay all day...let other hunters move the deer for you...take a snack (trailmix, apples --stay veggie based) and enough water...also take a book (read a paragraph / look carefully around...repeat)--the book actually aids in concentration and keeping you still...video games/phones can work, but in lower light conditions they tend to backlight your face...
There are so many tricks and techniques that everyone on the forum could tell you something new, in the end you have to spend time on a stand watching deer and even other hunters... Best of luck ...
David