What works for me is to draw the feathers on with chalk.
Of course, that is, if your background is not white! I do not like using coloured chalks.
No, I don't FMQ exactly on the drawn lines, but it does give me a guide and sense of what I am doing.
Especially around corners.
Another hint ... draw a chalk line set in far enough from your binding line, so that your FMQing, feathers or otherwise does not extend into binding.
The chalk ... mostly comes off as I work on the quilt.
At the end ... I just use a clothes whisk to brush away the rest.