Using a set of Kwik Cricket or training stumps, remove the middle stump. Make a decision that you're both going to bowl one side or another and both bowl that side. We both bowled over the stumps in this illustration. Then mark out a zone into which you're going to bowl, we use a mat. The zone/mat needs to be wider than the stumps and placed on a good length to bowl. As both bowlers look down the wicket from the bowling end they've both got a fair equal area onto which to bowl, one side shouldn't favour the other.
So the off-spinner bowls as per this illustration below - landing the ball on any part of the mat but aiming to hit the furthest stump, so with the offie he has to hit the leg-stump so encouraging him/her to turn the ball as much as possible. We play it - giving a point for landing it on the mat (A) and 3 points for landing it on the mat and hitting the designated stump (B). If the bowler hits the easier stump no points are given. Needless to say you could easily modify the rules and give points for the nearer stump too.
For the leg-spinner (Me) I have to pitch the ball on the mat (C) and turn the ball into the off-stump (D) to get maximum points. The way we play it is if the ball hits the stumps having gone straight on we still get 3 points.
Needless to say this only really works if you've got a good few balls. But it's good in that it's competitive and encourages bowling on a good length spinning the ball hard enough to hit the furthest stump. Looking at it, you could if you had some white tape mark the mat out as below and award even more points for landing it in the outside zone and hitting the opposite stump? The variations and possibilities are quite varied.
Check out my other blog here - this is all about Leg-spin bowling and nothing else. Double click on the image below.