when cutting the notches the new thought is to simply snip where the notches are. once or twice or three times, however many they show. then just line them up with pins for sewing.
for cutting on the lines: unless you will be making more than one size from the same pattern, the easiest way to mark is with a highlighter:
find the line indicating the size you've chosen for that part of the pattern (i.e. size 8 for the shoulders and neck, but size 12 for the bust) and with a highlighter, blend the sizes together to create one smooth line for cutting. you would follow the size 8 line and blend it into the size 12 line. one line will be dotted for example and the other dashed for example, so they are not that hard to find. just blend.
tracing paper: unless you have darts, you shouldn't even need them. but, if you do, place one paper on the table face up against the wrong side of the fabric and the other face down against the wrong side of the fabric. follow the new blended lines (if you did that) with the tracing wheel, which is a handle and what looks like a spur attached. the points on the spur makes little dots through the tracing paper onto the fabric, so you can see where to pin two layers together or where to mark a point as on the point of a bust dart.
it sounds like a lot of information, but once you've done it, it will be easy.
my recommendation is to learn one method at a time. the first should be the sizing, not the darts. once you've sized correctly, the whole thing falls into place.
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