This is a great question and is often asked around the startup community. At a recent event, the three main ingredients the panelists concluded for fundraising are: 1) have a good story, 2) be prepared and 3) build relationships
You can start talking to investors now to build those relationships. Don't start by pitching to them, start by asking for advice. Be genuine.
A big milestone you want to get to BEFORE actually pitching is having a very tangible dollar amount that you need to get to the next milestone for your business. I call it the "rock-solid plan" when your financials line up with your marketing plans, product roadmap, and hiring plan.
Investors that do believe in you will want to know that the money they give you will get you to milestones like: Early Revenue, Product Market Fit, Cash Flow positive, etc.
