Explain all abstractions and generalizations in definite, specific, concrete terms, but do not overstate. Use third person predominantly. First person is used for papers centered around personal experience or opinion. Second person is used for directions given to a participating audience. Use past tense predominantly also.
Present tense is used for statements that are universally true.
Future tense is used for that which will be true in the future. The reader will immediately feel the incompleteness of the composition. No, . . . . and similar constructions. Simply tell why. Use abbreviations carefully and sparingly.