First of all, there's the machine.  This uses hydraulic pressure and an electric motor to ease the process, but you will still need a valve core remover, tyre lever, clamp and tyre mounting and demounting paste.  

• Inspect the machine by checking the condition of the cable, level of hydraulic fluid and that everything is working and ensure the tyre is fully deflated before the demounting process begins.
• Put the wheel assembly on the machine and apply the clamps to fix the rim face.
• Use the roller to break the bead first on the outside.  Once the bead is broken, apply the demounting paste on the flange and bead.
• Change the position of the roller so you can break the bead on the inside of the rim. When that's done, come back to the first side, fix the hook on the tyre bead, and by using the hook and lever, the rotation of the machine will remove the bead from the rim.
• When that first bead is removed, apply the demounting paste to the inner side of the tyre bead as you rotate the mounting clamps.  Change position again and use the roller to push the bead out of the rim flange.  This demounts the tyre from the rim flange.

• It's time to inspect and clean the wheel. You're looking for cracks and any other obvious damage.  It's always best practise to replace the valve for continued reliability and use a stud hole gauge to check the wheel stud holes are still the correct diameter.
• Check the rim flange with a rim gauge. This is important on alloy wheels because they tend to wear.
• With part-worn tyres pay particular attention to the condition of the beads and check to make sure any repairs are sound.  Also, check to see if anything has penetrated the tyre.  This might have led to secondary damage which could result in a zipper failure when the tyre is inflated. 
• Ensure there's no foreign matter inside the tyre and only refit tyres that are legally compliant.  

• Paste both flanges on the rim.  Using the clamp and hook you must mount the first bead from inside.
• If the clamp, hook, tyre and rim are positioned correctly, start rotating and this movement will mount the tyre onto the rim.  Reposition the hook and clamp and then it's the same process for the other side of the rim.  
• Then it's time to inflate the tyre. In a workshop you should always inflate a tyre in an inflation cage.