We would like to sign authors in the future, but we are not accepting any submissions just yet.
In the meantime, it is possible to do the whole thing yourself.
You can typeset your work, and produce Advance Information sheets, with the very reasonably priced Affinity Publisher (don't listen to anyone who says you need InDesign);
You can join the non-profit Alliance of Independent Authors, where you can find very good-value proofreaders and cover designers, and you will also get free codes for self-publishing;
You can send an Advance Information sheet to booksellers (and you will probably get at least a sympathetic hearing at your local bookshop if you're a regular customer).