Figuring out side top and side under spin serves

Having trouble returning them.. I understand the physics of it but always not angling the bat enough. Either closing it too much on a side under or not enough on side top spin..

Any rule of thumb for tackling them.. knowing speeds?

Sorry I was a bit lazy before:
I think this was my most comprehensive post on it
Hope it helps!:-
(Hookshot referred to below has also done some good stuff just search)

The thing is experienced players rely on instinct. That is they watch the serve and they just react based on the thousands of balls they returned in the past.
They ACQUIRED the instinct by applying the principle that hookshot described in practice.
In addition try to look at the bounce of the ball a topspin ball tends to leap forward while a backspin ball
tends to 'sit up' a bit Get your partner to serve simple backspin or topspin from behind a board and try to read it from the bounce after a onth or two you will build up your 'instinct'.
Another tip is to not worry about the sidespin as long as your serve return is smooth and positive THROUGH the ball tends to go where you hit it. But back spin and topspin are critical because you may go in the net or off the table.
rule is:
backspin and back/sidespin serve: push under or lift(topspin)
topspin serve:drive or smash or block over the ball
pure sidespin serve: treat as topspin that is go over the ball with attacking shot
short serve: use guided return with neutral vertical racket face looking to flick if you can.

Lastly think like an artillery man!
in the net? up abit on that serve next time
off the end down a bit.
you are building your INSTINCT
If table tennis was easy we would be doing something else!
you'll get there!

Also watch closely where the server is contacting the ball, if you touch the same spot on the ball it will kill the spin then you can put your own on the ball.

if he touches the top, u touch the top, if he slice the bottom, u slice the bottom, if he chops the right side, u also chop the right side. Not mirror images, exactly where he touches it, you touch the same place.

If it's a pendulum serve (racket moves in U-shaped pendulum), then watch the contact point. When the pendulum is on the way up (late contact point) then it is topspin. If it's early, it should be underspin.