Today, I have three sigils for you. Each of them is somewhat different in its attitude and purpose, so I will discuss each and leave you to practice with them.
The first sigil, shown to the left, is a mode of communication and means of congregation with these beings. They are found in nature and tend to wander & slither about, following flows as they are driven to do so.
Serpent spirits are of the land, and thus have become aware of magnetic currents and how those currents impact magic and its practice on the day to day. If you'd seek to invite them in to your life, place this sigil as you feel is appropriate.
The second sigil, shown to the right, represents an offering and an invitation. Where the first tells them they are welcome, the second demarcates that something is for them to use and enjoy, be it tea, coffee, or incense procured especially for them.
After a time, when you've given them ample reason to trust you and your intentions, you can diversify and delve more deeply into practicing magic and all manners of spirit work with them. This, however, serves as a kind of practical introduction.
Finally, we reach the third sigil, placed to the left. This is, by and through its nature, the most active of the three.
By its shape and through the intense energy bound up within, you can likely feel that this is meant to get to work. This sigil is red and active unto itself, representing taking something up into a serpent's coils. Mark this on yourself when you are ready for them to become one with you. This is how and where you will begin to learn how they work and why.
This is a serious undertaking. Do not treat this lightly.
They aren't necessarily harsh or wrathful in nature, but they are relatively serious about their teachings and what they bring to the table. These beings have been marginalized and demonized to such a degree that they don't often like people. If you feel this is not for you, I would suggest staying far afield of these practices for now. When you're ready to do so, you can return and take up these sigils as keys into their kingdom.