There's a fanclub presale (currently happening), then mobile presale and after that they have the general sale. You will have to log into HMV Japan tickets & search for BAP when it opens. Then go through the steps, pick a date & fill out your info. You might have to have translate the site if you are unable to read Japanese. You also might need a Japan zip code & phone number but you can get a phone number from an app & since you receive the tickets from a convenience store you can just pick a zip code.