No reason to be dismayed if you do not have naturally big hands to grip the ball hard and get vicious turn. Try these things if you have slightly smaller hands but still want to be a great off-spinner.
1. Focus more on developing deceiving lengths and flight
Try and beat the batsman in the air rather than from the pitch. How does that work? Vary your speed and flight and see which one troubles the batsman the most. And also make sure you have an excellent arm ball and faster ball (no long fingers required!). Have a look in my book at developing these variations. Bowl them more than the usual off-spinner. Massive spin is bonus an not essential. If you are a regular club player you can take hundreds of wickets by just having a deceiving flight, subtle speed variations and a killer arm ball. If you can add a normal ball that spins enough just to beat the bat, then you can become a great bowler.
2. Strengthen your fingers
What comes as natural to other guys - you need to develop. So, make sure you get the maximum strength from your fingers and wrist by exercising them. This is easy to do - just use a tennis or squash ball and squeeze it as hard and as often as you can. Keep one in your cricket bag and pick it up when you sit next to the field watching your team bat. And of course make wrist strengthening part of your weight training in the gym.
3. Develop a wrist doosra
Very hard to do, I know. Very few people manage to do this. But it’s not dependent on big hands, but rather on supple and strong wrists - so do give it a try. This is the type that Saeed Ajmal likes to bowl out of the back of the hand. For a few guys it comes natural. You might just be one and you wont know until you give it a try. No long fingers required as most of the spin is in the wrist.