Reibun
、、、。

Remove the cap from the ink refill bottle, draw up the ink with the dropper, and drip an appropriate amount onto the marker's absorbent element.

Literal

Ink refill-bottle [gen-の] cap [obj-を] remove, dropper [with-で] ink [obj-を] draw-up, marker [gen-の] absorbent-body [to-へ] appropriate-amount, drip [request-ください].

A dense instruction sequence chaining three actions with masu-stem conjunctive forms. スポイト 'dropper' (from German 'Spritze'). 吸収体 'absorbent body' is a technical compound. 滴下する 'to drip/instill' is a precise technical verb. The whole sentence is structured as procedural instructions — each step joined by the conjunctive masu-stem.