Here is a great tutorial one of our members posted on how to do meander marking with no stencil
https://www.quiltingboard.com/blogs/...ng-b12853.html
As for when to mark, like NJ quilter, it depends on what tool I use. But if I were hand quilting a meander like that I think I would use a water soluble marker like the blue mark be gone or crayola ultra washable marker and mark the whole top out before sandwiching. That way I run no risk of the ink seeping into the batting while marking and I will also keep the size scale somewhat even.
But if I were to use a meander stencil like is found on this page:
https://fulllinestencil.com/product-...inner-designs/
These stencils are made to be used specifically with pounce.
https://fulllinestencil.com//product...y/pounce_pads/
I would mark as I go with pounce or pounce ultimate chalk
Here is also a starter pack that has 4 stencils (one of which is the meander) and the pounce pad and chalk
https://www.sewingmachinesplus.com/t...QaAunwEALw_wcB