If you don't know what the OS-Railway is, it's a fully 3D-printable railway system, check other models here: https://www.thingiverse.com/groups/os-railway/things
This is a 10 part slope for the OS-Railway system. The aim of this slope is to reach the same height as the two published bridges in the following links:
Truss bridge: https://www.thingiverse.com/thing:2624578
Arc bridge: https://www.thingiverse.com/thing:2172709
The arc bridge contains a slope with more massive pillars, you can choose that one if you prefer that look.
If you are going to use this slope together with only one bridge, you don't need the 140mm pillar because it's the same height as the bridge. It is intended to extend the track at the same height as the bridge(s).
If you need to print separate parts you can find all individual parts in the included ZIP-file, otherwise use the STL's called "complete_pillar_xxxxx.stl".
Not much instruction needed, it's a simple print. Use 0,2 - 0,35mm layer height. Be prepared to sand or cut a bit to make the pillars slide down into the base. It is supposed to be hard to get them in though, that's intended to make them sit tight without glue. No support needed. The holder joint can be either screwed using countersunk M2 or glued to the track joiner plate. I glue mine.