Witness voting

Hello Steemians!!

I am fairly new here and ever since I've joined everyday I have learned a thing or two about steemit.

So far I've noticed that steemit is mostly run by bots and if I pay a bot upfront with SBD I get upvotes, irrespective of the quality of post, makes life easy for me.

I learned today that I have 30 votes for witness voting at first I was clueless about what these votes are. I did a quick search on steemit and found some helpful post that gave me an idea of what witness voting is for.

Now, I am a new user I don't know any of these witnesses and none of these witnesses know me, how do I know who deserves my vote?

Any help to clear this dilemma will be great.

Thanks in advance.