Anything I should Add to Wall Before Adding Insulation Board?

Clear OSB at the moment on the internal side. I have an excessive amount of DPM left over.

Was wondering if there is anything I can add to the summer house wall before hammering in the insulation board to make the insulating properties a bit better?

For example stapling a sheet of DPM to it, or adding that foil bubble wrap stuff?

The insulation board I ordered is a bit smaller than the stud wall width so I have space to add something else if it's gonna make a difference.

Cheers.

Normally some sort of sheet goes on the outside of the studwork wall panels. I use sark IT sheet built from the bottom upwards, usually 3 strips with an overlap. Then the insulation is pressed in place from inside and OSB/ply/interior cladding over the top.

The DPM will be useable in place of the Sark IT sheet.