To Check your memos, type "/msg memoserv list"
To read a memo, type "/msg memoserv read <memo number>"
To delete a memo, type "/msg memoserv del <memo number>"
To remove deleted memos, type "/msg memoserv purge"
To send a memo to a registered nickname, type "/msg memoserv send <nickname> <message text>"
For even more information on MemoServ commands...  type "/msg memoserv help"