Hiya, I'm Paleo and I just started posting here a couple days ago. I've only just started my new channel 3 months ago, but I feel like I can give people some advice since I have had a bit of experience.
Before my advice, I'd like to tell you a bit about my history. You can skip this if you want, but read if you're interested!
I'm no stranger to youtube. I joined back in 2006 and started uploading random videos for the world to see. Most of them were footage of aquariums and sometimes experiments with making music videos. Never had many subs, only got up to 100 but had a lot of views due to particular interests some people had with dolphins and orcas since I took footage of them quite a bit.
Much later on in 2011, I decided that I wanted to focus on being consistent with uploading videos and really looked up to people who made an effort on the site. I made a new channel and started doing vlogs every Monday, Wednesday, and Friday. They weren't very focused, but eventually around 3 months of uploading videos, I was able to find my niche within the fan community of My Little Pony: Friendship is Magic and started reviewing episodes of the show.
Now, like I said, I have a new channel I just started 3 months ago that I forwarded my old subscribers to visiting. The retention rate wasn't quite as much as I'd like (going from 20,000 subs to 2,000 subs feels like quite a downgrade), but I gotta remember these things I learned throughout my youtube career and I think you all should to:
1. BE CONSISTENT
I think this one is very important because I see a lot of people not sticking to a certain amount of videos uploaded, when they are uploaded or even what their video subjects are about. (It's important in the very beginning to try to have your channel focus on a niche, it's much easier to gain viewers that way.) I think it's healthy for a channel to have around 2-3 videos a week, any more and it might drive viewers away unless you have really good content. I see people uploading a huge amount of videos way too often. If you really want to get views, wait for a video to settle for a while, the views will come. Don't wait too long though, because huge gaps between uploads can be very offputting to potential subscribers. There are exceptions like with some animators or musicians, but if you're doing something like let's plays or vlogs, stick to a schedule.
2. BE SOCIAL
This piece of advice means two things. First, it means to promote your content on any social networking you may have and ask for help from your friends. When I first started posting videos, I'd ask my friends to follow and like and I posted on facebook. Eventually I found a forum that pertained to my niche and I posted videos there.
The second thing is: don't be afraid to interact with your audience and message other youtubers. When I got to around 500 subscribers with my old channel, I found some guy named Saberspark who made similar content to mine, and he was around 1,000 subs, so I messaged him about collaborating and now we're practically best friends. I see him at conventions whenever I can and we talk on skype constantly.
So yeah, message people who make similar content, you'd be surprised how many friends you can make. It really helps to collaborate.
3. BE PATIENT
This is probably the most important one. It takes a very long time to get any traction on youtube when you're first starting unless you're god-tier amazing at what you do. It took me 7 months before my channel really started to go somewhere, and for the next couple years, I was able to get to 20,000 subscribers and 2,000,000 views with that channel. I had to take down a lot of videos due to copyright claims since I reviewed a t.v. show and fair use is kinda weird on youtube, that's why I made a new channel with a new focus, but still! I was able to get to a substantial channel size is what I'm trying to say. But it takes a long time.
So overall, my advice is:
1. Make sure you are consistent with your videos in both how many uploads a week you have as well as the subject matter.
2. Use social media (and your friends) to your advantage to spread around your content, and try making new friends through youtube!
3. It may take a long time, but eventually you will get to the place you want to be. It just takes dedication.
I just wanted to share a bit of what my experience has been like with youtube and what advice I could give to you!
you are awesome man 
