You do not need an AMS to change colours. At the layer where you should change colour, change to pause and manually change the colour when the print pauses.

Bookmarks need a clean plate to avoid any corners rising.

Project: Rockies.hfp
Print at 100% infill with a layer height of 0.08mm with a base layer of 0.16mm

The Model is 46.5x140mm in size
You may print at higher layer heights below the Min Depth of 0.64mm
The Max Depth is 1.3mm and the Actual Depth is 1.4mm

Filaments Used:
    PLA Generic Black
    PLA Generic Baby Blue (very pale blue)
    PLA Polylite White
This print uses 3 unique filaments

Swap Instructions:
    Start with Black
    At layer #9 (0.8mm) swap to Baby Blue
    At layer #10 (0.88mm) swap to White for the rest.