I do a lot of 172/PA28 checkouts with guys coming from the airlines or the military. Most take 3-5 hours for people in your situation. My tips for success would be as follows

1: It's all you. Preflight planning, checking the weather, deciding how much fuel to bring, running a weight and balance. I spent an hour with a gentleman doing W&B last week who is a professional pilot who just hadn't done it in awhile. If you get Foreflight it will do it for you though

2: Plan, but don't over plan.

3: Understand your limitations. Though it may take just a couple of hours to get you safe in a small aircraft again, it will take several more to become truly fluid and proficient. You probably don't want to tackle a large, gusty crosswind just yet. If you want to fly IFR get a separate IFR checkout as avionics can either be older and simpler, newer and complex but more capable, or old and downright weird. Again, you're on your own as far as IFR flight goes.

4: Think safety. If the airplane is questionable, don't go. If the weather is questionable, don't go. If your abilities are questionable, don't go.

5: Have fun! Go get a burger in the next town. Take your kids friends for their first airplane ride. Enjoy not having a schedule or passengers to please. Just go fly because it's fun.