Bring copies of essential law to the courtroom
Trial judges have a voluminous amount of statutory law and caselaw to digest. Judges are generalists, switching gears from one day to the next and one case to the next with criminal and civil cases, and a whole host of civil and criminal kinds of cases.
Being human, many judges will mis-apply even areas of law that are well settled. That is harder for them to do when a trial lawyer not only has copies of the most relevant caselaw and statutory law available to hand the judge and opposing counsel, but also at times a trial brief or short relevant typed summary of the relevant caselaw.
Also being human, I suppose that not all judges review new appellate caselaw and statutory law as closely as they should.
The lawyer needs to be fully familiar with the caselaw and statutory law that s/he cites to the judge in order to hit the persuasive point home, and also in order for the judge to rely on that lawyer as a credible and reliable source for quickly boiling down the relevant law to its necessary essence at trial.
The foregoing may seem basic, but I repeatedly see lawyers not only not bringing relevant printed law ready to hand the judge, but also grasping for such straws as: "I think there is a case on this point, called something like Rexrod or Redwood or Redd Fox."
Nothing beats nor replaces daily reading relevant appellate caselaw from the jurisdictions where one practices. I do that daily, and often find gems that way. Reviewing caselaw daily is a much more manageable endeavor than waiting weeks at a time to do so.