Postecoglou's Spurs were the early pace-setters in the Premier League this season and were top of the standings after going unbeaten in their first 10 games, but the London side have since been winless, picking up just one point to drop to fifth.
"The pressure is the pressure, it's always there. I've never let it guide my path or way forward. I've got a clear idea about what I'm trying to do and we'll keep working methodically," Postecoglou said ahead of Sunday's game against Newcastle United.
"I don't have a three or five-year plan up my sleeve that is guaranteed for success. What I do have is a plan that will get us to where we need to be.
"How long that takes, I don't know. It depends on how we keep discipline in staying the path.
"There will be another challenge in six months time. It's about how committed you are to go on the path you've started.
"I'm not wavering with that, I will not budge. That's what I believe is the best way forward."
Spurs average more shots per game than every side except Liverpool but six teams have out-scored them this season while Thursday's 2-1 home loss to West Ham United was their fifth successive game where they squandered a 1-0 lead.
"From the start of the season I don't think we've rewarded our dominance with goals," Postecoglou said.
"Even the games we've won we haven't really converted the opportunities or created the chances our play should have. That's still the area where we have a hell of a lot of work to do.
"I still think our front third, we've got a lot of work to do. Unfortunately, that's costing us in terms of results."
But Postecoglou has had to deal with several long-term injuries, especially playmaker James Maddison and Dutch centre back Micky van de Ven, who are both out until January.
"We've had some challenges within that time frame with injuries which have disrupted our ability to have a consistent lineup, players out who had started the season well and were very influential," Postecoglou said.
"With all that context, that happens to every football club, we've just got to work our way through this difficult period but we're still at the beginning of what we're trying to build."
