what do I have & how ,where to clean?

A set of Redfield International mk 8 irons came with a mod 70 target I bought, included was a Hensoldt,Wetzlar screw in iris? the thing is adjustable with amber and clear settings, I shot the set up on my win 52C today and was impressed, did good at 50 and 100 yards, it will adjust and really focus on front sight, My question is how to clean the thing properly and how is best way to really set the thing up. thanks in advance[;)]