Titan, if you're refering to the Basic Sampling tutorial on this site, you're right, there is something missing:
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Trimming
After sampling and naming, we need to trim the sample,to get rid of any space at the start and end. Go to the TRIM page by pressing Shift and 5. There are 3 ways to trim the sample. One is to type the start and end numbers in - very impractical in most situations, another is to use the jog wheel - good for getting the final edit points, and the third is to use the note variation slider. Simply hold down SHIFT and move the slider, and the edit points move big distances. I suggest using your middle finger on SHIFT and your thumb on the slide. This way, you can do most of the editing with the slider and use the jog wheel for the more detailed bits.
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Before you can start trimming your sample in the Trim page using the Shift button and the variation slider, you first have to press the EDIT button (F5).
