As a newbie who is making your first investment in bitcoin, I expect your first buy to be in lump sum or possibly an aggressive buy in order to have a reasonable amount of bitcoin in your portfolio.
for most newbie, the DCA method would be the best approach they will consider as a means of accumulating Bitcoin but it's going to be difficult for a newbie to start his bitcoin accumulation journey with a huge purchase because they are just new to the system and are more concerned on how not to expertience serious loss because most of them are not just new to the forum but are new to the bitcoin industry and would want to invest small amount first while they monitor to see that they get the first returns that will serve as a motivation to enable them accumulate more.
I'm not saying a newbie can't start his bitcoin journey with huge purchase because in the real sense the amount of bitcoin one accumulate is more about how financially strong one his and ones ability to taking a reasonable risk.