• Drill hole to the correct diameter
• Chamfer hole.  This will assist the tap to enter the hole
• Start with the No 1 Tap (taper tap)
• Put some cutting paste or cutting fluid on the tap and into the hole
• Make sure that tap is square to the hole to be tapped.  Use engineering square or sprit level
• Turn tap clockwise one full turn and then half back.  This is to ensure to remove cuttings
• With blind holes, regularly clean hole of any cuttings.  Be careful when using compressed air.   
• Repeat process with no 2 and no 3 tap

Tapping using the drilling, milling machine or centre lathe