Unfortunately, there's no easy answer. Long story short?
1. Study the sectional of the area you're planning to fly (and other maps, if you want).
2. Pick checkpoints you won't be straining to see that you could possibly miss, even if it means finding a "cluster" to act as your checkpoint.
3. Don't be sloppy flying. You need to be on your heading and stay there, or you can easily wander off your course. You'll need to know nearby landmarks or be able to look at the sectional or a map that will have landmarks on it so you can find your way back if you really wander off or get disoriented.
@April Evans - are you flying with GPS as primary or paper sectionals as primary? I found that the act of doing all my preflight planning on a sectional really helped me understand what I was going to see and what I needed to look for. I trained in rural Iowa/Minnesota, and there was a distinct lack of good checkpoints. I usually flew by using a pilotage system I called "triangulation of points". I would pick two to three checkpoints in one area that would create a unique combination, such as a road that had a "ess" bend to it, with a railroad crossing the turn, and a tower on the other side of the line I wanted to fly. I would then fly through the point where the lines met in the middle. It wasn't an exact science, but I was flying VFR, so I could adjust if I was slightly off course when I was coming up to my next checkpoints. Studying the sectional to pick good checkpoints helped immensely, because I got a good sense of every town, tower, road, and railroad track along my route. I flew with paper as primary and GPS as back up, because I found it easier to navigate with the sectional. If I was ever in doubt as to where I was (which happened on my solo xc), I could say, "To the east is a railroad track crossing a road at an angle other than 90* and a meandering creek. To the west, there's a small town with a grain elevator and a two-lane highway running through with a funny bend right before the town. To the south is a lake and some windmills. To the north is a private strip with a bunch of hog barns near by. Now, which of those things do I see and where?" Once you locate yourself by finding those things, you have a good enough guess as to where you are that you can adjust back to the course you'd planned. Unless you have a better GPS than I did training, you can't do that with the GPS.
As for getting disoriented, know which headings you need to fly to get to where you're going, and which directions your airport and your destination airport are. If you have a rough idea of where those things should be, it's easier to find them when it seems like everything is just a big jumble. It will get easier as navigation becomes a more normal brain activity and as the flying itself requires less brain power. I was pretty disoriented at my first couple of lessons, and navigation was entirely up to my CFI. I was pretty worried I'd never be able to find my way through the sky, but after I knew roughly how to fly the plane and had studied the charts so I had a better idea of what I'd be looking at and for on the ground, it progressed from a challenge to a non-issue by the time I was doing solo xc work.