The skin test is given into and just under the skin, in the same was as a test for TB is sometimes given.
The test is primarily for a delayed hypersensitivity response. In other words you are not likely to experience a sudden allergic reaction.
If you are sensitive the area of injection will usually become red over the month after the injection.
The manufacturer provides a small card that allows you to communicate to your doctor the amount of response. If you are allergic this card is returned to the manufacturer.
It is not painful and is felt as small sting.
Afterwards the small lump in the skin dispapears over a week or two.
There may be slight redness at the site of the test for a few hours.This does NOT mean you are allergic.