A beginner in need of help/advice

Submitted to Ask the Makers

I am brand new to power carving. I have a Dremel 4000 with the flexshaft. I am wanting to know first how do you know what speed to use when using the Dremel? I have a few bits and they say max of 25k but for like diamond bits and the regular dremel round cutters how do you know what speed setting to set the Dremel at?
Second question is I am just wanting to start simple and learn to do script/lettering and do some basic designs. Does anyone have a first project that they would recommend that really helps learn all the basics? Thank you for any help you are able to give it is much appreciated!