You can apply for 9 IDs to create a character, plus one of your own IDs (if you have multiple IDs, you can apply for a few less, or ask your friends to use trumpets with different IDs to help sign). When creating a new guild signature, you cannot use different characters with the same ID to sign. Only one character with one ID can sign the same guild application. Characters with different IDs cannot sign the same application form, nor can they sign different applications. However, characters with the same ID can sign a second application form with another character after the guild signed by one character is successfully established. Trial accounts cannot sign guilds. This is how my own trumpet guild found the IDs of several friends to sign for my school guild (I have three IDs). Because I tried signing with different accounts with the same ID, but it didn't work.