When convenient, make notes on calendar, note pad, roster, program, etc. What you talked about Person's interests, job, family, etc. Can keep permanent notes in rolodex, address book Review the next day and week until the name is known. Use your friends' names daily in conversation, even if silently. MAME Acrostics - first letter of each name stands for a word in a sentence.
More bizarre sentences are easier to remember.
Keep a file or notebook of names for each of your activities or groups. Review before each meeting. Make a simple association or find substitute words in the person's name. Link the person's prominent feature with their substitute word in an unusual mental image. Bizarre or unusual images are easier to remember.