dear bikelet,
I presume the tape you are talking about is the rigid therapeutic tape.
There are more than one way of taping, using the non elastic therapeutic tape and using elastic therapeutic tape (known as Kinesiotape).
dear slowsider,
Would always suggest you have your shoulder checked by a physiotherapist first.
You may need more than a tape only.... and assessment results wil indicate which type of taping will be best in your case.
Evidence regarding the effect of both tape types is meager.