Ait oke, well I think Facebook is the best tool to spread your mixes/tracks when starting as a dj. Just for the simple reason almost all the people I know are on the platform. I use Soundcloud to upload my sets, but also read some good stories about mixcloud. So my advice is to find a place where you can easily upload your music and spread it on the social platform most of your friends are on.
After that the first thing to do is build a website, doesn’t have to be difficult. Just a simple website with your contact details, music and a link to facebook is a good start. When you’re playing somewhere you can tell people to go to your website where they can find everything they need. After the website is done you can always add other platforms like twitter etc.