Preparative

a.	1.	Tending to prepare or make ready; having the power of preparing, qualifying, or fitting; preparatory. Laborious quest of knowledge preparative to this work. - South.
n.	1.	That which has the power of preparing, or previously fitting for a purpose; that which prepares.
	2.	That which is done in the way of preparation.

Adj.

1.

preparative - preceding and preparing for something; "preparatory steps" Synonyms: preparatory, propaedeutic

preceding, preparatory, propaedeutic