Some good info on here. I will throw in my two cents. I grew up in southeast MT and rifle hunted mule deer in my teens and early twenties. In my early thirties I lived in Bowman, ND and started bow hunting. Early season mule deer can be very difficult. Summer herds with many eyes. It can also be a great time to kill a mature deer that's left the herd early. If it's hot, hunting will be tough. Find them early in the morning. Hopefully the weather cooperates and the deer are moving for you. Be in descent shape. Sometimes you need to cover some nasty ground. Like others said glassing is a big part of it. Don't be afraid to sit in one spot for awhile. Stalking is a big part of it. You don't have to take all your gear off when stalking. Personally I keep my boots on. Keep some gear with you so you can adapt to the situation. Wind is an even bigger part of it. If the wind is wrong it's not worth it. Take a buddy or two and yes watch out for cactus and rattlesnakes. Don't set expectations so high you are disappointed with the deer you see. Although there are some giant deer out west. Knock on doors, introduce yourself, and ask for permission if you need to. The worst that can happen is they say no. I have successfully spot and stalked two mule deer during 8 years of bowhunting. It's tough. If you make a stalk and it doesn't work stay positive. It's easy to "lose it" after 3 hours of waiting, crawling, and waiting only to have the deer bolt on you. Again, adapt to the situation. I love hunting those big eared buggers, they are an incredible challenge, but you can have success. Good luck.