Once you've located deer trails, look for tracks. If all the tracks are going in the same direction, follow the trail to determine where it goes. Depending on where the food source is, you might have found the main trail heading to the food source. It's helpful to know how far deer are traveling from the bedding area to the food source.
Deer sometimes enter a food source on one trail and leave on another. Other trails might be used both as entry and exit routes. You can study the tracks to determine what kind of trail you've found.
If you're hunting a field, set up in the morning on a trail the deer are using to travel from the field back to the bedding area. In the afternoon, set up on a trail deer are using to travel from the bedding area to the field.
When hunting pressure gets heavy, it's good to know where the deer are bedding, as they become nocturnal. If you hunt a morning stand near a food source, the deer might leave the field and be past your stand before daylight. If you hunt an afternoon stand near the food source, they might not come out until it's dark.
If you set up near the bedding area, you have a better chance to see morning movement back to the bedding area at first light. You also have a better chance to see an afternoon buck moving toward the food while it's still daylight. If you can find two or three trails that merge into one trail, you know you've discovered a great place to put a stand.
Also keep in mind that big bucks might not use the main trail. Look for less-used trails that parallel the main trail and watch for that smart old buck.