If your hike is taking you across a beach you should seriously consider wearing sandals unless conditions don't allow for it (ice cold water, sharp stones, etc.). If you wear boots consider using gaiters to keep water and sand (well too much sand) from entering the top of your boots. Moisture combined with the tiny grains can leave your feet raw and sore.
To aid in keeping your pace up you should walk in two different regions over a beach. If you can handle having your feet damp you should walk in the region where the surf rolls up the shore. The water packs the sand down so it is firmer, giving you more power with each step. If you don't want to be in the water than consider walking where the forest or field meets the beach if it is a practical solution. If you're walking in soft, shifting sand you'll need to be methodical with your pace, step slowly to let your standing foot settle into the sand so you don't get exhausted or worse twist an ankle. A person in average condition will only cover five to eight miles on a beach in a day. 
Muddy, wet, damp, marshy trail or ground Crossing marshy ground poses a number of interesting problems. Mud with no vegetation on it can be as slippery as grease. Soupy, squishy mud can literally suck the shoes off of your feet and wear you out. Dampness can soak through your boots bringing you to a dead stop.
If you're moving through a wet, muddy environment the object is not to get to deep into the mud. If you sink in up over the top of your boot the suction created can rip the boot right off of your foot. Try to follow the path of previous hikers, or avoid it if they left deep postholes behind. If you're walking on slippery mud trekking poles can be a big help, but make sure they have adequate baskets so they too don't posthole. Gaiters are almost a necessity to keep the mud out of your boots and keep you dry. Unless you enjoy really gross experiences, leave the sandals, trail runners or sneakers at home. In really soupy conditions don't expect to move more than five to eight miles in a day.
Rock strewn, boulder fields, dry rocky river beds If the rocks you're crossing are bigger than baseballs you're going to be in for a rough ride. Rocks can shift posing a real fall hazard and increase the chances of an ankle injury. Balancing techniques and trekking poles may not be enough, and over extreme terrain, trekking poles can become a dangerous liability.
I think it goes without saying that if you're crossing a rocky area that good sturdy boots with excellent traction and ankle support are key. If you're crossing large rocks like glacier till at a terminal moraine be prepared to get on all fours and scramble. Like moving on a rough trail, make sure the foot staying on the ground is firmly placed before taking your next step. If you're carrying a heavy pack you'll want to have your center of gravity be lower, so heavier gear should be toward the center of the back and near the bottom. Crossing rocky terrain can slow your pace down to a crawl, don't expect to cover more than five to eight miles in a day if you are in average health.
The most important thing is to walk a pace and style that you are comfortable with. If you find you're falling a lot or you have twisted your ankle in the past evaluate your hiking technique. A lot of accidents happen because hikers are rushing or fatigued. If you find you're dragging your feet, stumbling or taking risks slow down and take a break. The distances traveled above assume a person in average health carrying 25 to 35 pounds of gear. Experienced through hikers can cover as much as thirty miles in a day under ideal conditions, while a person in poor physical shape may struggle with three. With a little bit of technique any terrain is passable allowing you to find new adventures further down the trail.