If you have any questions, don't hesitate to ask! This image is downloadable to print out to scale (if you have the paper to do it). If you do print it, I hope it comes out okay! If not, just draw it freehand with the measurements I provided for you. I hope the measurements make sense for you - I did my best >.<
If you made a collar with my template, please share! I would love to see your outcome!
Sorry for asking a dumb question here but, since the "front" of the collar isn't "pointy", how will it look when done or am I just totally lost here? (My english isn't so good, not sure if you know what I mean ><)
The front of the collar would be under the Bow or it could be folded and sewn under the front of the leotard, so you won't really see it, but it should sort of taper to a V. However it's easier if it is over the leotard/under the bow for easy removal. You should also sew the two ends together with the right sides together so that it has a nice finish. I hope this answered your question!
I wouldn't use a shirt at all. The shoulder seams of a shirt would completely ruin it and depending on your size and the it's specific shape, there probably wouldn't be enough room on the shirt itself to cut it out from the back and the front because you have to double layer it.
If you want to make it out of cotton for a school uniform (rather than a Sailor Senshi Uniform) I would highly recommend going to a fabric store and buying fabric in the colour of your choice to make the collar