First of all, understand the composition and responsibilities of the student union, as well as the operation mode and election rules of the student union in your school or college. Usually, the members of the student union are elected by the students themselves and need to run for election and vote.

The following are possible steps:

1. Pay attention to the official notice and recruitment information of the student union of the school or college, and know the recruitment time and method.

2. Prepare your own campaign materials, including personal profile, campaign manifesto and plan. These materials need to show your strengths and commitments, while paying attention to concise, clear and convincing language.

3. Participate in the training and planning meetings of candidates, and learn about the rules and procedures of the election, as well as the responsibilities and rights of the student union.

4. Actively publicize your campaign materials and plans during the campaign, communicate with voters, and strive for their support and trust.

5. Take part in the voting of the Student Union, strive for more votes and win the election.

6. If you are successfully elected, you should conscientiously perform the duties of the Student Union, serve the students, give full play to your ability and influence, and constantly learn and improve your organizational and leadership skills.