i guess theres no clear cut formula, but this is what i do:
introduction
paragraph about (for me, doing changing worlds) technological changes, introducing my texts
paragraph about core text for technological changes
paragraph on stimulus/extra on technological changes
paragraph about social changes, introducing my texts
paragraph about core text for social changes
paragraph on stimulus/extra on social changes
paragraph about language changes, introducing my texts
paragraph about core text for language changes
paragraph on stimulus/extra on language changes
conclusion
so..yeah, thats what i follow, and it works for me, i get around 17-20/20 for all my essays..but also try to increase your volcabulary and relate all your paragraphs back to the question..