Best advice I've heard, and the best I can give, is focus 90% of your time searching 10% of the areas. If the spot has something going for it, grid pattern the entire spot. I think so many people think walking ten plus miles a day will yield results, when they'd be better off hitting the good spots several times over.
Another thing is to pick your spots. Spending all day walking a couple hundred acre field is frustrating and time consuming. Instead, look for specific spots that might attract deer or give deer some cover in an otherwise wide open area. I'll make sure to pick apart wet spots with reeds growing, small ditches, anything holding water, or the base of a steeper hillside. Small pockets of woods in fields are great spots. Also, while I normally don't walk many deer trails, I'll hit each one entering a field for at least fifty yards.
South facing slopes are ok, but I prefer east or southeast facing. Most of our winter days are gloomy and windy, so I feel like deer aren't as focused on basking in sunshine that doesn't exist, but rather getting out of the cold prevailing wind.
Pine trees, especially pine forest pockets can be awesome, but usually only if the pines are smaller and bunched together to create a thick canopy that will block rain and snow.
Keep in mind that I live in Ohio, so this advice might not be applicable in southern states.