There are 3 main parts to the forming of a sigil, The wording of your sentence of initial desire, conversion of you sentence in to visual representation and implantation of you sigil in to your subconscious mind.
Of those 3 desire is the most important and the most difficult due to the make up of the human subconscious, The Sentence must be concise, using just enough words to express the meaning.
And it is the letters of this sentence that you will use to create your sigil
The most simple technique of creating your sigil or glyph from this sentence is to cross out all double letters contained in your sentence of desire, then graphically combine your remaining letters to create your sigil.
To make the sigil work it is in a way opposite to charging, it must be introduced to the deep mind. The simplest way is to hold the image of the sigil in front of your eyes and stare intently at it, and at the peak of gnosis absorb it in to the mind.
DarkMaster explained , "popular" new-age "chaos" method or making sigils
Traditionaly they are made by inscribing them on certain KAMEA/S then copying them to parchment using right magickal ink or blessed pen , vibratting word of power or the very sigil word and visulizing energy flowing into sigil. Than the sigil is carried in puch bags ( mojo bags , hex bags or medicine bags ) burnt or used in other manner.
Some inscribe them on candles. Sigils are not always words translated to numbers and thpose translated via KAMEAS to sigils , they can be runes , bindrunes , combined alchemic symbols , enochian inscritions , occult themed drawings etc