Help him with LN custodial as a first step ( most people should not clog onchain with small tx ) onboard him by showing various lightning apps he would potentially interested ( fountain, stacker news, fold maybe or anything )

Self-custodial would be pain in the ass for first-learner. I can't give you much since i've yet be able to onboard anyone🥲

Help them with cex that support LN ( Kraken, Bitfinex or Binance ). Would be a long way to introduce him to P2P markets like Bisq or Robosats

After one month show them rugpull of the past to spark his interest in self-custodying his own stack. Phoenix is good since it's not that complex & ACINQ already take care of the user's SCB

Start with NGU narrative maybe help ( it's gold that can teleport anyway ). Once enough people adopt Bitcoin then using it as a medium of exchange would be instant-click

:)