First, Minibus #1 goes from IFC to The Peak - i.e. up on the hill, upper Peak Tram terminal. NOT lower Peak Tram terminal near Central.

And currently, I do not recommend taking either Bus #15 or Minibus #1 to the Peak if time is tight. Traffic out of Central can be bad for buses and minibus.

Instead, the preferred way is to just WALK from IFC to the lower Peak Tram terminal. Through the HSBC building, up escalators to Cheung Kong Centre, than along Garden Road past the St John's Cathedral, cross Garden Rd and you're there.

Coming down, I am not kidding you, but if the line for the Peak Tram is super long, a fast way to Central is by walking down Old Peak Rd (right next to upper Peak Tram terminal), Albany Rd and Gleanely. 25 minutes and you're in Central. Faster than the 15 bus with the uncertain traffic. Minibus #1 is still faster coming down.