Just beat a pusher 6-3, 6-2 and you will all say that is not very impressive. That is my first point of this post, if you go out onto court expecting to destroy a pusher, win every point and win without trying, you will lose. In my defence I have won 8 in a row in my local singles league, 7 of them against junkers/pusher but I also dropped a set in most of those matches. Give pushers and especially junkers respect, otherwise you'ill lose.
What made the difference for me is I have stopped trying to blast pushers off the court from the baseline and embraced the short ball. Unless you are having a very good day, you are not going to overpower a pusher from the back of the court. Instead use your superior spin, power and control to move them about. Useless you say because a damn pusher never misses, so what is the point of moving them? You're doing it to get them to cough up a short ball you can actually attack.
It is much easier to beat a pusher when you are higher up the court because it takes some of their time away. My standard tactic is pretty obvious, get on the forehand, target their backhand corner and wait till they hit short. In the old days I would have either blasted long or into the net at this point, I dreaded the short ball. The reason I did this is I tried to hit a winner with sheer pace, I felt I had to hit it really hard to beat the human wall.
Don't do that, you are not playing Djokovic, it doesn't have to be that good. Instead pick a spot on the court and aim to place the ball there. Yes hit it with spin and a bit of power but don't blast it. Hit in a controlled way. I basically aim for these places in that situation. Down the line, short angled ball or straight at the pusher, depending on where I am on the court. The last sounds nuts, straight at the pusher, after all they never miss but it works. Do it right and it is like a body serve, they can't get out of the way.
Don't be afraid to take a leaf out of the pushers book, if you are off balance or in a bad position, swallow your pride and play defensive. For example, I struggle to generate pace with backhand, so if I get a paceless ball on the side I can't run round, I hit a deep slice to stay in the rally. If I am forced backwards from the forecourt, I run back and hit a moonball to stay in the rally. You have to believe you are better than the pusher and not be afraid of staying in the point till you can take control back.
On the serve I actually play two spin second serves, one hit harder than the other. This sounds crazy, why give up potential free points against a human wall? The reason is, the pusher very rarely hits a double fault, so if you do you can find the score board pressure starts to build up and crush you. I have confidence I can beat the pusher in the rally, so I don't need to risk missing the serve.
On their serves I recommend moving up the court, standing so most of the service boxes is on your stronger side and really attacking it. Just like the short ball, place it into one of the spots. The pusher is often most vulnerable straight after their service action and it is a good time to try and get the ball past them.
One last piece of advice, don't get lazy and stop moving your feet. If you expect the match to be easy and disrespect your opponent, you will lose. I am still guilty of this myself. For example I lost a point when I hit a very good backhand drive down the line. I was in the lead, so indulged myself a bit. I stood their admiring the shot like I was playing golf, never expecting my opponent to run it down. He did, shanked it off the frame and it turned into a dropshot down the middle and he won the point.
In the old days I would I have been outraged, how dare the damn pusher win that point, it wasn't fair, it was a brilliant shot. This time I was outraged at myself, I lost that point due to my arrogance, I should I have expected the ball to come back and moved so I had a chance of doing something about it. The pusher played well, they played good tennis, they put the work in and got the ball back. It was my fault that happened and I congratulated my opponent on his good play.
Basically I am saying, if you want to win you have to put maximum effort in, accept pushers are tough opponents and don't get down if you lose games or even drop a set. Be confident in what you are doing and most of the time you will eventually get the win.