Hi Steemians
There is a whole industry dedicated to musical instruction, everything has been covered a million times and in most cases not a lot of it actually has anything to do with You sounding like.. well - You.
One of the most obvious things that beginners especially are left behind on is vibrato, the act of raising and lowering the pitch of a played note with your left hand fingers (if you are a RH player).
I'm not going to go into too much detail in this post about the hows but I will post some suggestions here with a video to follow up when I am able to record on the weekend.
Vibrato really does set guitarists apart, from Kirk Hammett's nervous and erratic vibrato to Gary Moore's amazing subtle to screaming command of the technique, to Steve Vai's very idiosyncratic and expressive approach - The way You approach it and hear it in your head is very personal and it becomes a major identifier of your sound, it also is a way you can really wear your influences on your sleeve.
I suggest watching a few videos on youtube, the examples above are good searches to start with and vary quite wildly in their applications.
I know this post is a bit basic, but the idea is to introduce the concept of vibrato as being a large part of Your voice on the guitar (or any instrument that is capable of pitch manipulation) and to hopefully inspire You to look around at what others do and to focus your ear to one of the more obvious idiosyncracies.