I have done this top in a different yarn (Classic Elite Flash: Lotus being discontinued, I think and there being no Classic Elite available in my area in Oz). It is a bamboo cotton mix - 8 - 12 ply but not twisted (plied?) AT ALL - split city! It splits very easily and if it snags goes totally crazy.

I tried doing a weaving (mattress stitch ?) join by the instructions in Stich N Bitch Happy Hooker... a) I don't think I got it quite right, b) the yarn kept snagging (it was joining a decreasing angled side to a decreasing angled side so the edges were both quite bumpy) and split and went crazy, so I had to pull it out and try again.

Next, I tried whipstitch. I had wrong sides facing me and whipstitched - my understanding being that would put the seam on the inside - however it seems more visible on the outside.

I am not sure what to do to join this, and I'd really like it to come out well (and soonish) - it is my first go at a garment for me (other than a shawl)...

Can you give me any tips?