The less you touch the lens, the better. Even if you don't scratch it, modern lenses have a number of invisible anti-flare layers on them to improve contrast and light which you will be affecting with each wipe.
Use a blower, compressed air or a pen-like instrument with a special tip that the dust sticks to (usually sold as digital cleaner).
Failing that, gently use an anti-static brush.
If you are going to use cloth and liquid for tough jobs, be certain to use the right kind and put very little liquid on the cloth NOT on the lens and use it very gently.