Are you finding the confetti stitching / many colour changes make it slow progress? I usually park and I also grid but on my current project there are so many colours in just one block that I have switched to cross country stitching because there were just so many parked threads I had to part them like a hairdresser! and couldn't find where to park my next thread.I have also started gridding blocks of five within the blocks of ten. Might seem like overkill but it has really helped speed up my "hunt and peck" of all the confetti.
Another tip to cut down on the bulk on the back because of starting and ending so many different colours is to use the pinhead stitch.
Thank you so much for you replies. franacropan hit the nail on the head. I find with so many colours that I tend to get 'confetti stitching' as well as so many parked threads making the back a complete mess.
And something I use with my Haed, is different markers. I have 5-6 colors to mark with. They aren't bound to a symbol, but I work with one marker for the first color in my 10-10 grid, then take another for another symbol. I find it easier to do it like that.
Also, don't try to get caught to do a lot off confetti stitches at once in one color, cause it happens sometimes that you are adding the second or fourth... symbol on it and noticed they are a stitch or 2 to much to the left/right/bottom... Better work in grids then in long lines or big covers.
I hope this helps you a bit, I'm not stitching for very long yet, but this is how I do it.