How to get used of trackpoint on a thinkpad?

I would just recommend practice.If you are having difficulty pinpointing the mouse on small areas, I would suggest turning down the sensitivity.

I found that using a concave rubber cap on the trackpoint helped a bit for accuracy.

There are two types: the standard flat or slightly convex caps, and concave caps which are available as original accessory. For me, concave caps provide a reduction of "free travel" because the cap is more shape-adapted to the fingertip. So after starting to move the finger, the delay before the mouse pointer starts to move will be shorter than with convex caps.

This is just my personal experience, but I would avoid using the trackpoint. I used the trackpoint equivalent on my HP laptop a lot when I first got it. I was hooked on Free Cell and spent a lot of time moving cards around. After some days or weeks, my right index finger started hurting a bit and feeling numb, so I started using my middle finger instead. Soon it had the same symptoms. I couldn't grip anything with my right hand. I stopped using the trackpoint and the all the symptoms gradually disappeared. I think I was lucky.