First of all let's select a 3x3. The cubes shown below have been hand picked as being great starter cubes. They're fast, controllable and stable.

Secondly, we need a timer. Speedcubing Timers are a great way to accurately record your times. You can't be using you phone or a stopwatch anymore.

Lastly, it's always good to have a mat down to protect not only your table, but also your cube. When you stop your timer you tend to slam your cube down too.