In this thread
http://www.coffeecup.com/forums/respons … eakpoints/
are views exchanged about standard breakpoints. Depending on where the lay-out breaks you have several different points in your stylesheet , i.e. the menu, content, sub-grids and whatever. My stylesheet is rather long by now and the switching up and down in the stylesheet is somewhat tiresome. I am beginning to think of writing mediaqueries directly in the concerning element. What is your view on the best practice in this case (besides using Sass)?

I write mine in various places depending on the need. If I only need a few I place them near the original rule but if I'm in need of several I place them at the end. I'll even write a separate style sheet if each page requires a lot of unique queries.
A lot depends on your need for speed or clearer code so you can easily make changes.

During development, I create several spreadsheets and link to all of them. This makes it easy to find what I need. When the project is completely done, I combine them into one and just link the pages to that one. That way there are fewer requests on the server and the page performs better. It's the best of both worlds for me.

I have done this in the past, but it can quickly get out of hand. Now I put a section at the bottom of the CSS file for all media queries and try to keep them in some order; sections or flexbox stuff first, <h> tags and text next, maps, slideshows, etc. last.

Sometimes I make a separate CSS file to work the media queries out in first, then move it into the main CSS when done.

Thanks guys for feeding my thoughts. I appreciate it.