Having done my Night Rating recently I would advise trying the following.
On the later stages of final approach begin the roundout a little earlier adding a little bit extra power if neccessary, to maintain your threshold crossing speed (approx 65kt depending on Aircraft).
By executing the roundout a (little) earlier and then flaring more slowly and progressively the aim will be to achieve as low a rate of decent as possible whilst close to touching down.
Obtaining accurate Visual cues and achieving good spatial awareness is generally more difficult at night so avoiding high rates of decent on the later part of the approach will much improve your chances of a gentle touchdown instead of harsh bounces or collapsed nosewheels.
