'Sign how [fingerspell word]' with quizzical/questioning facial expression.
Sign (as in sign language not a poster/sign or to sign, there are a few meanings on this page) https://www.signbsl.com/sign/sign
Hope this helps
Good morning everyone! I am deaf-born ASL signer who is interested in learning BSL. Long time ago I taught myself BSL (and also JSL) alphabet by heart, but never got to learning BSL itself. I am looking to set up a language exchange video sessions with native BSL signers if possible. I am interested in learning more about deaf culture and deafness in UK.
Hopefully I'll make some friends here! Nice to meet you.