I’d start with economic security policies like buying brick and motor investments like gold. 

A ruthless pursuit of food security.
expansion of North sea oil licenses plus a hard-core approach to fracking. 
Complete suspension of asylum from nations and concern and allies. 
Seizing all assets of foreign nationals of concern with enforced travel restrictions for them and immediate family.

Also a rapid expansion and recruitment of the police force
Redirection of billions towards security services and intelligence