These aren't high maintenance, you just have to understand their most basic needs. You can't use ordinary potting soil. For mine, I use 50% silica sand & 50% peat moss. You can buy a bag of silica sand from Home Depot for about $5. Just ask them where they keep their pool filter sand out in the garden center. Don't get just any sand. The pool filter sand is 100% silica, which is completely inert and won't harm your flytraps. For the peat moss, don't use the Miracle Gro brand. Never use Mirace Gro brand anything for carnivorous plants. It can be any other brand, just as long as it doesn't have any fertilizers added to it. Never use any fertilizers, which is why Miracle Gro is always out of the question.

To prepare the peat/sand mix, I like to scoop up more than enough silica sand than I think I'll need. Place it in a small bucket and fill it up with hot water and use something to stir the sand around, before draining away the dirty water. Do this several times until the sand is rinsed out and much cleaner.

For the peat moss, soak it in a small bucket of water and stir it around pretty good. Let it settle down some and scoop out only the peat moss that floats on top of the water. Squeeze out as much of the water as you can. Do this until you have as much peat moss as you'll think you'll need. Don't use the peat moss that has separated and sunk down to the bottom. Use only the stuff that floats on top of the water.

Mix the rinsed out silica sand and peat moss half and half, and use this to repot your flytraps into a larger pot. Venus flytrap roots grow straight down, so use a pot that has some depth to it. I would recommend a plastic self-watering pot, because their roots can't be allowed to dry out. Plus, having a self-watering pot would encourage your flytrap's roots to grow down in search of more water.

One last thing to remember is don't use ordinary tap water for these plants. You can use distilled water, which you can buy it from any grocery store for cheap. For mine, I collect and store rainwater whenever it rains, and use it for my flytraps. Ordinary tap water can kill carnivorous plants. I use ordinary tap water to rinse and prepare the sand/peat moss mix, but then I always flush it out with rainwater after I've repotted my flytraps.

Once you have it repotted, just place it in a bright, sunny location and give it some time to recuperate. It's perfectly normal for their old traps to turn black. They will continue to grow new ones to replace them. I usually just pinch off the black traps and leave the rest of the leaf to photosynthesize.

I hope this helps, and if you have any questions, then feel free to ask away. Once you get the hang of it, you'll see that flytraps are fairly easy to grow and just so fascinating to watch.