Don't forget Mastodon! We're already here on Lemmy after all, may as well mention the properly federated alternative too.

Also want to piggy back because if this is a sona, do you (OP) have a clear idea of what you are or look like? The more time you spend figuring these things out, writing detailed stuff down, making crude sketches or perhaps editing bases, the more likely whoever it is that you speak with will be able to bring your idea and identity to life. Whatever mediums work best to help you visualize your sona, will also help the person drawing it. In this way, both of you have less headache making changes, or being dissatisfied with results.