Training Forehand without Return Board

With regards to practising forehand topspin. You could; if you have a table tennis table or table that is spare to use and a few table tennis balls at home, practice the stroke by throwing the table tennis ball vertically and hit the ball as though you would in a game if you wanted to put topspin on the ball. By doing this you can practise not only the contact that you need to make on the ball (a brushing action), you can also practice the timing of when you should hit the ball to make sure it goes low over the net (as well as placement on the otherside of the table, that is if have a table tennis table, not if you don't, obviously!).  

I used to toss the ball to practice my forehand, but then I realized that this is training the timing the wrong way since in an actual match, the ball would be moving toward you not just forward.  If you can, you should get underspin on the ball so that the ball comes back to you and then try to loop that, but that might be hard because you have to learn how to get enough underspin to get the ball to come back first.