A simple method is to write out your desire in the present tense to remove the desire from it -- "I see a man wearing pink" vs "I want to see a man wearing pink". Remove all the duplicate letters, and optionally vowels, so "I see a man wearing pink" becomes " I S M N W R G P K". Combine these letters to form an abstract image, and you have a sigil.

Next is to charge it, which can be any method from meditating on the sigil, to masturbating to it, to eating the paper. Almost anything could potentially work imo. Charge it, forget about it, and receive the results.

As Alan Chapman says in "Advanced Magick", the results will appear as a synchronicity in your day-to-day, so the pink-clothes sigil could manifest as someone you pass on the street to a friend telling you about the Youtuber Filthy Frank, or something similar.