As with the wand, the practice today would have me inscribe these sigils upon my athame.
I actually do know some of these sigils. There’s a description of most of them in the Fararr’s A Witches’ Bible. The first is that of the Horned God. I’m not sure what the second is, but the third and fourth are the kiss and the scourge. The sideways crescents are a goddess symbol, but I’m not sure what the top/bottom crescents are for. This particular arrow sigil means that power flows from the God, and the star is the symbol of the 8-fold path. Still, I’m not inscribing sigils on my athame until I’m asked to as part of an initiation. If I was to do so, though, here’s how Roderick suggests going about the task:
Begin by inscribing two red candles with the athame sigils. Set the candles in holders on either side of you and light them. Light some fire incense and then dab yourself with fire oil at the center of your solar plexus. begin the athame inscribing process. You can do so with pain, an engraving tool, or by magical infusion.
While inscribing, split the focus of your attention between your work at hand and the energy of your solar plexus region. Sense the feeling of energy that runs through your body at that chakra point. If you notice that your mind drifts from the shared focus of inscribing and sensing the energy, discontinue inscribing the athame. Take three deep breaths and realign your awareness.
If magically inscribing the runes, take a third red candle and inscribe it with the athame sigils. Light it and pass the blade briefly through the flame, chanting “By the blessed thirteen moons, Sealed are ye by sacred runes!”. Continue with this until all the sigils on the candle have been melted. When this is done, write the sigils in black ink on a triangle of red paper. Set the paper aflame, and drop it into a burning vessel. Take the cooled ashes in your dominant hand and rub them along the blade.