Good question...
The ability to control your dreams is a very advanced way of self-suggestion. Some people who study Metaphisics are able to day dream and plan in advance how things are more likely to go based on inducing positive thoughs so vivid that it is hard to tell the differnce between what's real and what's not.
A very simple excersice is to ask yurself frequently "Is this a dream or real life?" during the day. If you do it often enough, you will find yourself asking the question while you are in the middle of a dream. It is tough to keep concentration enough to be able to control your dream, but it possible after a while.
I was able to do it more often when I was younger. You know, the mind of a kid is always in the clouds. 😉 As an adult, it is more complicated because you tend to rationalize everything. It has been a while since I have been able to fly in my dreams... 🙂
Anyway, It only takes a fraction of a second for you to be able to introduce tickling in your dreams. If you can make yourself realize that it is a dream you are into, you can quickly self suggest that you go an tickle whoever is near you. It works!
One interesting thing is that sometimes in "real life", you find yourself wondering whether you should/could tickle that person besides you or not. It actually makes you more proactive with your tickling. I have had a lot of positive experiences...
There is a lot to be said about self-suggestion and the ability to control your thoughts and mind to a level. It can bring you a lot of good things to your life, and I am not only talking about tickling. 🙄
Take care,
Knight Tickler