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

The Model is 50.64x152.46mm in size
You may print at higher layer heights below the Min Depth of 0.64mm
The Max Depth is 2.5mm and the Actual Depth is 1.4mm

Filaments Used: I do not know the TD numbers.
    PLA Black - Creality Ender Series
    PLA Blue - Polymaker PLA+

    PLA White - PolyTerra PLA+ 

This print uses 3 unique filaments

Swap Instructions:
    Start with Black
    At layer #12 (1.04mm) swap to Blue
    At layer #13 (1.12mm) swap to White for the rest.