Sewing from point to point!

It can be challenging sewing a straight line from a particular point to another particular point without some for of reference except the ending points. The Manhattan Bag below has seams sewn on the folds of the bag and represent the technique I am addressing:

 When you have the purse panel flat, you sew from point 1 to point 2 to point 3, and to finish at point 4. There are no guide lines. I put pins at all points and simply sight from pin to pin and sew for it!!!!. 

Sometimes, I press crease marks from point to point, then sew on the crease lines.  This works pretty well.

A third method would be to use seam tape or some kind of 1/4" masking tape. The following picture shows what we mean:

I tried to put tape on all three seams but this particular tape started to fall off before I could finish the seams. Though I love this tape, a different tape might work better for this technique. I sewed right next to one side of the tape.