hi guys, i'm totally confuse of build backlink for my authority site. so, i had create content that on-page optimize, and for next, i'm planning to get some backlink (tier1) from edu,guestpost, etc. so, the question is, should i use tier 2 to get PA for tier 1? and should i continue to make tier 3 to get PA for tier 2? or if we just make tier 1 without tier 2, it will be good for boost ranking our site on google? if no, what type or advice from you to make tier 2 ? thank you guys. i hope your advice.