Title says it all
What you will need.
Step 1: Go Out and Buy a Good Sketch Book.
Always use this before you try anything with markers or if you will permanent markers (Not the whiteboard type)
Step 2: Choose a Name.
Its a lot easier to start off with words, have at the most 4 different words and no more, keep on doing them until you feel like you have mastered it, this will help create a feel when you are doing a non word sketch.
Step 3: Evolve You Drawings/words
A lot of people want to start off by doing figures, it does not work out like that, you have to chance it and adapt it too you style that suites you. I have made one for demonstration i used my name as you can see i have adapted it with colors and patterns.
Step 4: Buy Some Perament Markers.
I would suggest Krink, Markwell, Molotow, and On The Run.