If you're looking at having a good experience, learning, and filling your tag on a decent buck (rather than hunting big bucks exclusively), here's a big-timber formula you might consider:
1)
E-scouting: Get OnX maps, and look for logging cuts (patches of cleared timber), and burns about 2-4 years old. Big timber isn't great for feed growth - feed needs sunlight, and dense timber doesn't get much on the forest floor. Logging cuts and burns provide this sunlight, and generate the young, fresh feed muleys need. Cuts and burns are deer magnets in dense timber. You get a similar effect at the edge of tree lines when you get into higher altitudes. Hunt the edges, hunt the cuts, hunt the burns.
2)
Cut sign: Once you find some likely places, cruise the dirt roads that run their perimeters next to the tree line, looking for deer tracks, especially buck tracks. If no roads, walk the treelines - you'll find game trails leading right out of them. When you find them, look for routes of travel between feed and bedding. The more heavily traveled, the better. You're looking for a route that has several distinct sets of tracks of different individuals, not a lone doe wandering around with a fawn or yearling. Cutting sign like this is critical in saving days of time glassing areas. Dismiss entirely any notions of getting into that timber and hunting it. Unless you're at an elite level, you're just not going to get into that timber and hunt them in their beds - plan on an ambush hunt while they move their regular routes to and from feed. Also, don't worry about finding their water sources - muleys quite often go for days at a time without water, but they feed every single day in a race to survive the winter. The less heat and direct desert sunlight they're exposed to, and the more green around them, the longer muleys go without watering. Focus on finding their routes to and from food, and the feed sources they browse. The closer you are to their bedding area, the more likely you are to see them coming home in the morning, and leaving to eat in the evening.
3)
Set up your hide: Once you find a good travel route, scout out a place to set up a hide overlooking this route somewhere - know the prevailing wind directions, try to keep the sun at your back, don't skyline yourself, make sure you can shoot from different angles and directions in it. Once you find a good spot or two, scout your approach routes to your hide that will keep you clear of those travel paths - both visually and your scent. You don't want to be stomping through their feeding areas or their bedding areas on the way to your hide. You want to be virtually non-existent to them in every way in how you approach and sit in your hide, and how you leave it to go back to camp. Know the wind directions cold, and have a couple of routes to get into your hide when wind is coming from different directions. To really do this right you need to know where they're bedding and where they're feeding, before selecting a hide site.
4)
Arrive early: Be in place
at least an hour before sunrise, and plan on staying until it's so dark you need a flashlight to get out. October deer tend to stay put hard during daylight hours, especially during really hot weather. Your best chance of catching one on the move is probably going to be in the first 15 minutes of legal shoot light, but you want to be well settled in long before that. As to staying late, even if you go past legal shoot light, you may very well still learn something by observing any deer movement after that - there's often another half hour or so past legal shoot times where your binos will gather enough light to let you comfortably observe what's going on in your area. The better the quality of your glass, the better you can see in dim conditions.
5)
Be still, be silent, be scentless: It's hard to describe just how sensitive a muley's eyes are to movement, but if you pretended it was an AI-powered surveillance robot out there that locked its focus onto any movement at all, you might start getting an idea of how sensitive it really is. Even seasoned mule deer hunters underestimate this, in large part because the buck freezes or escapes long before they see it (they tend to freeze in areas trafficked by people, and move to escape in areas where people are less common), and have no idea how many deer they just alerted - they just keep moving on, clueless, thinking everything's fine because they didn't see any deer. If you absolutely have to move, try to move no faster than 10% as fast as you normally would. Even then that's too fast, but you get the idea. So go to extra length in your hide to set it up to be comfortable for hours of virtual non-movement, and for you to be as concealed as possible. As to silence, they're called mule deer because of the radar-dish mule ears they wield - they will hear a zipper or food wrapper 10x or even 100x farther than a human can, depending on conditions. The more out-of-place from normal the sound is, the more they'll alert on it. As to scentless, you'll never, ever be scentless - this is just shorthand for saying "you must play the wind". Always know the direction of the wind, at all times, and always keep the wind in your face. Because of this, you may need to have a couple of hides to play the wind properly, if the prevailing wind isn't consistent. If you have much altitude between your hide and the spot you're observing, also know how thermals carry scent when things heat up and cool down.
6)
Glass: Glassing from the hide is important, but it's not the same ballgame as how you glass desert muleys, or in hunting truly big bucks - this formula is for a good hunt and filling your tag, not so much about finding a monster. That's a very different hunt. But you should be glassing all day until you know the area cold. As part of this process, be using your range finder to mark out and memorize various distances to landmarks across your area of observation (unique trees, rocks, points in the treeline, etc). You want to know on sight how far a buck is, and you'll have plenty of time to do that your first day in the hide. It's still a good idea to use the rangefinder when a buck pops out, but sometimes your time might be limited, and this can give you a kind of backup edge. It's also a great way to keep your mind active and sharp while observing as well.
That's the best short-version of how to hunt timber deer that I can offer. It's an entirely different animal from hunting desert muleys, but it's been successful for me when I've had to hunt forested land. Hunt the edges, keep the wind in your face, don't skyline yourself,
go sloooow, and try to keep the sun at your back. You do all that, you've got a decent chance of success.
Someone who's active on here with a killer track record of forested Idaho muleys is
@Dioni A . Maybe he has some extra tips he might be willing to share.
