I recommend a signature card with your image to help build a personal connection with parents when communicating via email. Use any of the business card templates in Canva to get started. Design-wise I recommend sticking to a white background and downloading it as a transparent PNG file. This way, it will meld seamlessly into the page if the person uses light or dark mode on their computer. I also recommend looking at what the image looks like with a white or black background to get an idea of how it would look in light and dark mode.
Signature cards are also something you can have students create to teach them to become professional communicators. Especially in the first weeks of school, it can be so helpful to have a student put a face to their name when corresponding with teachers.
Here is mine as an example; each has the exact image/text, just one with a white and one with a black background to visualize the different user experiences.