"Tiptronic" is the name used by Porsche and Audi/VW for their manumatic transmissions. The Mercedes Benz version is officially called "Touch Shift" transmission.
The system is very easy to use. Just put the gear selector in manual mode and push the selector up (+) to upshift and down (-) to downshift. The system is electronic and it will not let you do something stupid like downshift to first while driving at highway speed or hold a gear past redline. The transmission will override your selection if you try to do something like that.