I often get told that I’m soft spoken, and I would like to know how to overcome this. I get frustrated constantly repeating myself, and having a hard time getting my point across.
As with all circumstances, you need to make sure that your voice is healthy and that you have no physical limitations, which a doctor can determine.
Physically you will need to work with your posture, the breath, the energy with which you bring your vocal cords together and the resonance. You will especially need to find the resonance that comes with humming and using a “nasty” placement. To develop all of these functions will take practice, commitment and endurance.
Mentally, you will also have to deal with your beliefs about speaking loudly and what you think of people who are loud as well as how you imagine people will treat you if you are loud. You need to determine that you deserve to be heard and have valuable things to contribute. In all of creation, your voice is utterly unique and is meant to be heard. That is also true of everyone else.
We all need to speak powerfully and listen carefully to one another, and to work through whatever emotions arise when we do that. I recommend you work with a coach who can help you not only with vocal production but also with assertiveness and belief in the messages you have to offer. You might even want to work for a short time with a therapist or a life coach to help you with the emotional and mental part of it.