Hello! This is a loaded question!
I have written many answers just here on Clarity and they should all give you a pretty good insight into how to do this.
https://clarity.fm/humbertovalle

I am a marketing strategist, MBA, and founder of a small hybrid digital marketing agency www.Unthink.me - my response for you is as follows:
First, ignore the answer below where it recommends you reaching out to family and friends. This is a horrible idea for more, especially if you are a shy person. This can lead to a false sense of growth with no real plan or factual leverage for new leads from friends and fam.
Instead here a few sample steps you must take no matter the focus, industry, or expertise:
If you lack a strong budget to advertise and position yourself properly through a market do the following:
1. Get yourself really nice business cards printed
2. Attend networking events and give yourself a few months of attending the same and meeting the same people and building rapport through out these events.
3. Learn to talk about what you do to those that care only.
4. Develop a personal brand, if you are starting out, locally you can be promoting yourself through those you meet as the helpful person, who goes out of their way to help other professionals. Helpful is always the easiest brand angle to get started with but its the hardest to live by so keep that in mind, but give it a try ;)
5. Uncover and discover benefits of your services you provide and turn those to investable opportunities to others.
6. Start a blog covering the plethora of questions prospect clients will have. Share this with everyone you know.
7. Instead of inviting people for coffee to be pitched at, invite them to get interviewed for a blog you and enter a dialogue with them about what it is that you do while giving them an opportunity to also share about themselves (assuming your cilents are professionals)
8. Stay honest
9. Stay consistent and don't deviate after a few tries. consistency is key to branding and to building trust.
10. Stay consistent - get it? it's important. Depending on many factors, your timeframe will be different from another person in the same exact position as you are. From mannerisms to luck to wording -- consistency increases your chances of not missing out on opportunities and referrals.