Think of reddit like it's another forum, a big mistake a lot of people make is post their link on the homepage and hope for the best. You'll hope till Jesus comes back
D:
Yes you can make friends if you want to, but it's not necessary. What you need to do is find a sub-reddit that is related to your niche. You can join a few sub-reddits if you want to. Just like in a forum, what you want to do is engage with the community in the sub-reddits you follow to build your reputation.
When it comes to getting traffic, reddit is really powerful than anything I've ever used online. You can post one piece of content and get traffic for 2 weeks or even more with just one piece of content. I'm not talking 10 visitors a day, I'm talking 300+ visitors every day!
But that will all depend on how you positioned yourself on the sub-reddits. It will depend on how those people trust you, your reputation and the comments you created.
If the people on reddit like you then there's no need to post every day or every week, just once in a while will work and keep helping others then you'll get the traffic you desire. Don't post your links on the homepage, post it in a sub-reddit that is niche related.
Also check when people are mostly online and post every time when a lot of people are online on that sub-reddit.
But offer a lot of value first.
WARNING! Don't post low quality content on reddit, ninjas there will eat you alive and you'll never get traffic from reddit ever again. No average content on reddit, make sure it's high quality and back-up your stuff with facts.
You'll also get a lot of opportunities on reddit, that's how I got my content featured on big websites and magazines. Reddit is powerful but never, ever, spam.
