Skin Prep for tattoo and piercing:

Step 1:  wash with soap and water 
Step 2:  wipe with alcohol or alcohol wipes. 

Method: Wipe in concentric circles from the inside to the outside
              using a fresh side of the wipe for each swipe. 

Washing is the most important part because the greatest number 
of microbes are removed from the surface during this process.
It is not the killing power of the antiseptic that does the most work.

If skin infection is suspected, wipe the area with alcohol repeatedly
and seek medical attention.  Skin infections are rare in tattoo and piercing 
and suggest that the immune system is not sufficient to defend against the infection.
Ordinary infections are minor, easily treated and do not result in morbidity or mortality. 
Antibiotics taken orally will usually be prescribed by your health care provider.
It is important to seek medical attention for any skin condition that is not normal.

Wiping the area with Alcohol repeatedly is "Best Practice"
until you can contact your health care provider.