If you speak confidently and in a manner that underscores a belief in what you are saying, you are likely to get others to agree. Meaning people want to follow the lead of someone that appears knowledgeable and self-assured.
Present a clear vision.
Another way to ensure that stakeholders listen to and respect your ideas is to present a clear vision. The vision is the compass for your project and the keystone of your idea.
The third way to be a strong yet informal leader is to be flexible. While you may be the one with the great idea, you must admit that you don’t know everything. So while it is key to state your point of view, it is equally critical to be receptive to the opinions of others. Listening to others is valuable because an outside idea may be just what is needed to make a good idea, a great one. Additionally, when you give people an opportunity to include their viewpoint in your plans, they are more likely to support the vision and goal you’ve laid out.
Be open to feedback.
Lastly, be open to feedback and solicit it regularly. Without feedback, you won’t know how your leadership is perceived by others and by extension whether it is effective. Therefore, take time to ask how things are going and check-in to see if people are still engaged. Getting feedback often, gives you time to course correct, if necessary. Furthermore, periodic feedback gives you a chance to know what’s working well and thus what you want to continue.
So while you may not have formal authority to get some things done, the strategies I’ve described are always available to you to informally and indirectly influence.