Don't do that.. Going around with a ghillie suit hiding is just asking to get yourself seen and the cops called. Chances are if you're walking around sneakily and someone catches you.. They'll think you're breaking into stuff and walking around looking for more. Find a small patch of woods or a field out in the middle of nowhere and time yourself from how long it takes to get from one end to the other. If it's a 100 yard field it should take you roughly an hour, if you're doing it any faster then slow down a bit, look around more often and check up at the sky and the trees (Wind speed and precipitation check). If you're doing it in 3-4 hours, then you're moving too slow for airsoft standards, here is the pace I do when I crawl.
Crawl maybe 1-2 yards (My body length), stop, put my head down (Keeping your head as low as possible is another mistake a lot of snipers make), keep it down for a few seconds, pending on how "hot" the area is. Then I look back up, look at where I'm going to crawl next, and look around for any sign of other snipers/enemy personnel, and then I repeat back at step 1.
Also, more good things to practice (I know this is going off topic on my end, might as well share what I know). Is in your spare time do box jumps, it will increase your vertical (How high you can jump) as well as make you be able to jump longer, once doing say.. 50 box jumps up an object maybe 2 feet off the ground is easy, put your rifle in your hand and your ghillie suit on. Then, make a small area that you can see how far you "can" jump, so if the time comes when you're booking full speed through the woods and you see that creek that looks 8 feet wide you can just walk back 10 steps and ace it.
Back on topic though.. If you can't shoot at your house, find a place nearby where no one goes that you know you can bust out the rifle and crack a few out. Remember, a consistent medium range rifle is much better than a long range finicky rifle.