I like the George Howell method: https://georgehowellcoffee.com/pages/brew-guide-chemex-six-cup-for-one

It's super easy and I've gotten great results using it for years now.

EDIT: Since I didn't fully read the title I mentioned my favorite hot method bonk. But for iced I use the same method except that I grind a little finer, use half the full weight of water as ice in the Chemex, then do the 3 pulses at half the regular amount of the recipe.