GeezerVison

If you also want the userbox to say that you write and post stories, fill the author parameter with 1, as follows:

{{User:SilviaASH/Userboxes/User Archive of our own|author=1}}

And the box will render as:

This user reads stories on AO3 and also shares some of their own there.

If for some reason you also want this userbox to link to your account just add your username like this:

{{User:SilviaASH/Userboxes/User Archive of our own|author=1|username=Example}}

Which will render:

This user reads stories on AO3 and also shares some of their own as Example.