Since its humble beginnings over a decade ago, World of Warcraft has centered most of the game through its social community. From questing in dozens of zones to taking on apocalyptic villains in raids, players are used to teaming up to tackle any obstacles. Because of these aforementioned reasons, players looking to streamline their experiences will often create a guild.
Existing since the early days of vanilla, guilds come together for a variety of PvE and/or PvP reasons depending on its like-minded members. Automatically being in a guild will grant certain rare rewards and bonuses such as being able to send mail instantly to other guild members. However, joining a guild requires an invite from someone else which means players with only one account can't add their other characters if no one else is online. Thankfully, there is another way to get that invite to alts without a middleman.
Start Recruiting
Players first need to open their Guilds & Communities tab by pressing the button with their guild logo in the bottom right corner of the display or just pressing J. Once the guild menu appears, click on the 'Recruitment' button to bring up another box. Check the 'List My Guild in Guild Finder' option and put an easily recognizable phrase for the Recruitment Message such as "just inviting my own characters to the guild". Hit 'Accept' and then log off that character. Be aware only characters at officer status or higher will be able to post the recruitment.
Apply to the Guild
Log onto the player character that needs to be invited and bring up the Guilds & Communities tab again. Click on the 'Search' bar in the upper right corner and type in the guild name. Hit enter or press the button below and the same guild plus description should appear after a few seconds. Click 'Request to Join', put any specialization down before hitting 'Apply', and log off the character.
Invite the Alt Character
Finally, log back into the first character and open up the Guilds & Communities tab. Click the 'Roster' button which should be marked by a little diamond and switch the 'Achievement Points' tab to 'Applicants'. The other player's reserve character name that applied should be listed and pressing 'Invite' will give them a pending option despite being offline. Get back onto the alt character and accept the invite notification in the top left corner to join the guild without any help. Kraken Latte demonstrates all the steps and how this can be used for a personal guild full of alts with her YouTube video above.
Although this takes a little longer than just asking for help, World of Warcraft players will inevitably find this shortcut useful when trying to invite their other characters solo.
World of Warcraft is available on PC.