I'm using Gunze flat clear H20 for my final coat on all me armour..well I'm not sure my technique is right or not..I add a mixture 1:1 that is 1 flat clear and 1 Gunze thinner..any other technique or mixture should I use..or don't use flat clear ?

Thanks

Sounds OK to me.
Do bear in mind though that it is always best to airbrush in none humid conditions.

yeah.. it occurs to me when water is spitted out instead of air.. due to the high humidity sometimes moisture trap is'nt just working well enough.

Generally I tend to slightly over thin my Flat clear so I can build it up gradually.
It ensures the kit doesnt look whitish.If it looks whitish add some smoke to the flat mixture then u can add shadows a bit at the same time.