I wanted to be section leader for Brass... But didn't get picked.
Anyway,
But I CAN help.
Steps:
A section leaders job is to act responsible. Like make sure your section has their sheet music,pencils, folders or other stuff.
Be nice. Nobody wants a MEAN person helping them.
Have friendly terms with your section. You don't need to be friends, just be sure their nice to you.
Learn your music. How can you help when nobody else knows the music?
Hold sectionals.
Help your section. If somebody has trouble on a note or something...Help.
Hold your section to their promises. If someone said they'll learn a passage by next Tuesday, they better have it down when next Tuesday comes rolling by. If they don't, ask them why they didn't.
Be understanding. If someone can't make it to the sectional because their grandma died, don't hold that to him. People have lives outside of marching/concert band.
Keep your section under control. This doesn't mean order them around, but when they get out of hand, let them know. If necessary, seek help from another section leader or the band teacher.
Listen to both sides of a conflict. If there's a conflict between two sides, you will probably have to be the third party to step in and solve it. If it starts to get physical, keep them apart and tell someone to get help from an adult as soon as possible.
Be on the same page as your co-section leader, if you have one. If you're telling your section something completely different than the other section leader, it will only confuse your section.
Tips:
Don't let other people in your section tell you or your section what to do. You're the one that will have more experience, thus you will probably know better than your section. Listen to advice, but make your own decisions.
Make sure you don't get too power-hungry; remember that being section leader doesn't mean you have to control every minute aspect of your section's lives.
Remember: A good leader is selfless. Take the blame; give the credit away.