It’s really hard to teach someone how to hire, how to manage, and how to lead. Like many things, it’s usually best to learn on the job, practice, and improve after making a lot of mistakes along the way. The problem is, as a startup, you can’t afford to make a lot of mistakes when hiring. You also can’t afford to wait too long to hire when the business is scaling quickly.

I thought I’d share my top three best practices when making a first hire (and in some cases, any hire). As a caveat, this is coming from a first-time entrepreneur, who has never directly hired anyone in the past, and generally believes in the goodness of man/woman.

1. For a senior hire, hire someone with experience. For a junior hire, hire the smartest person you can find. If you’re lucky, find someone who has smarts and experience. Our first hire was someone who actually had retail/online/consumer experience. This is something that I have had for exactly 2.5 years (since the company was founded). My co-founder and I knew what we were good at, but also knew our weaknesses. It was critical for us to find a person that could bring all the industry expertise and knowledge we could no longer fake. Our first intern (and eventual hire) was someone with exactly zero work experience. She was willing to work in whatever role we needed her for that particular day. She is also very smart. Although her role has changed over time, she was exactly the utility player every startup needs.
2. Take your time. Every single person we have eventually hired, including our first employee, has gone through a trial period with us before joining full time. This is not always possible, especially for a hyper-growth company. The point is that you want to take your time with your first critical hires. The people who don’t agree or understand this philosophy are  people you don’t want to hire. People truly passionate about a company in its early stages and truly passionate about filling a role for that company will be patient and understand the reason for a “trial period.” It’s not because you think they are mediocre or not the best possible candidate. It’s because when people believe in something, they’re willing to fight for it. That goes both ways, and is important to understand.
3. Fit is as important if not more important than anything else. Startups equal tight quarters, big personalities, too much to do, and too little time. If you have a virus in the mix, it can be devastating to a startup’s success — whether it’s a bad case of the chicken pox or a bad teammate. Find people you like to work with, because you are going to be spending more time with them than your girlfriends, boyfriends, wives, husbands, friends, and so on. Everyone does not have to be identical or like the same things. That can be a problem as well. Instead, they should fit together like a jigsaw puzzle — as complementary sides that work as a whole.

Side note: I have no clue if chicken pox is caused by a virus, but I thought it had a nice ring to it and I will check Wikipedia shortly.

The theme here is to hire with caution. New hires (and especially your first hire) can make or break your company. It should not be taken lightly. Building a team is one of the most important things you can do as a founder. If you’re good at it, it might be all you do one day. If you have the slightest sense that your first key employees are not going to get the job done or do not have the fortitude to survive a startup environment, cut your ties and fire fast. Personal relationships are the most important things I have in my life. But as a founder, I understand that I am running a business. It is bigger than myself. I have investors, customers, vendors, and suppliers to worry about. If something is not working out, fire, rinse, repeat, and build until you get it right.

This post originally appeared on The Huffington Post.