For the wood and wire lozenge decals I can say:
use light colour (white is good, light sand or something is also good)
because they are transelucent you can play with the colour.
I use Tamiya, so I use Tamiya gloss. Always use a gloss with decals.
they are VERY fragile, use very sharp knife to cut and be very carefull when placing. When dry coat with gloss to protect. I use Tamiya gloss and I use Tamiya smoke for shadow and finish with semi-gloss or matt
good luck