Read the draft of your eulogy aloud. If you have time and the inclination, read it to someone as practice. Words sound differently when read aloud than on paper. If you have inserted humor, get feedback from someone about its appropriateness and effectiveness. Remember, writing is 90% rewriting, so expect to revise your work several times before it shines.  Rehearsing the eulogy will also help you learn to control your emotions and not get choked up over the speech. Try memorizing as much of the speech as you can, or even just reading from notes. Though you should have something to fall back on if you forgot what you were going to say, your words will sound more heartfelt if you're not reading every sentence right off the page. Though you should hope that you're emotionally prepared to give the speech on the big day, you should have a close friend or family member who has read the eulogy be prepared to read it for you in case you're too choked up to read it. Though you probably won't need one, you'll feel more relaxed just knowing that you have a backup if you need one. Before you speak, calm yourself by realizing everyone in attendance is there to support you. It may help to have a glass of water with you on the podium to help you maintain your composure. Just know that everyone will appreciate your efforts and admire you for having  written and given a eulogy. You can't fail. Tell yourself you're not there to win a speech-giving contest or to impress anyone. You're there to convey your heartfelt feelings about the deceased and that's it. Talk or read your eulogy to the audience as if you are talking to friends. Make eye contact. Pause. Go slowly if you want. Connect with your audience and share the moment with them; after all, you're not an entertainer, you're one of them. There's no need to be formal when you're surrounded by loved ones who share your grief. Remember to sound like yourself, not some formal version of yourself. You can use a conversational tone as long as you don't use inappropriate language or too much slang that might confuse the older members of the audience.

Summary:
Rehearse the eulogy before the big day. Have a standby. Relax. Use a conversational tone.