Need stitch help

Hey guys im starting on a new project and I try to do everything by hand, so here is my dilema. I bought the material to cover my doors and headliner in my reg. cab 92 yota, i decided i wanted a nice pattern in it, i got a sewing machine and practiced till i got it right. Now my problem comes when i try to stitch the points on the cross. I tried asking my mother in law she didnt know.  Ok so here are the parameters as to why it is a problem. I dont want either color on top of the other and I want to make it look as if its all 1 flat piece. Oh and i want to do it myself. I do not wannt take it to a shop. If it comes down to it i will cover it with a solid color and airbrush the cross on there. Any help is appricated.
 
Heres the design
 
 

Sorry for the crappy pic, plus the design isnt perfect yet just a rough draft.

id love to help you but im not understanding exactly what your trying to do

I guess what i am trying to ask is how do i stitch the points? i can stitch the angles i just havent found a way to do the points to make them look good. If i do it the way i was doing the rest of it i end up stitching blind, which means i have to guess where the point is and if it looks good.

when you get to your stopping point do a back stitch.     I am not sure that your trying to do but i would look at having it embroidered.