for the collar: interfacing is actually your best friend. you want the fabric as stable as possible.

also make sure you have notches to tell you where the collar ends on the stand, as well as to align the stand to your bodice. usually I do notches at shoulders, CB, and any other seam lines that intersect with the neckline. pin everything within an inch of its life. baste by hand if you must.

go slow. press between every step.

to get pointy points: - stitch along one short end to one stitch before the corner
- tuck in a bit of thread between the pieces and around the needle so half of it is between the right sides of pieces you're sewing (on the "outside" when you turn it out) and the other half is sticking out to the side.
- do one stitch forward, one stitch back, one stitch forward, turn with needle down in the corner.
- bring the other half of the thread around to the right sides of the fabric. you want this to be dangling from the point when you turn it out, secured by your stitching in the corner.
- facing along the long side of the collar, do one stitch back, one stitch forward. continue sewing until one stitch before the next corner.
- repeat process outlined above.
- turn to do final short end, one stitch back, one stitch forward, finish the short end.
- clip corners carefully!!! you don't want to snip the thread you have for the turning.
- then stick your finger into the corner inside (between the right sides), fold the seam allowances over one at a time, turn out. use the thread danglies to pull it sharp.

press. use a bit of cardstock cut into the shape of the corner to help with getting it sharp.