There is a lot of unpopulated, very fertile land in the region south of the Firth of Forth. Offer some of this land to wealthy and powerful Anglo-Norman nobility. Build more monastries to bring Scotland up to scratch with England's religious communities.
Put your Norman friends into offices everywhere in your kingdom. This will root out all native Gaelic lords and encourage more Anglo-Normans from the south.
Find a nice young debutante and marry into a powerful Anglo-Norman family. This will lend you political alliances and may encourage them to join you in Scotland.
Which card will you play?