Aim issues

I've always had the same problem in any FPS games. I am just not very good. I've been through a couple upgrades (both my mouse and mousepad) and had a drastic improvement. Now, I have days and days, some I'm having tons of fun even against good players, others, I just cannot land a single shot and feel dumb and useless.

But there is something lingering in my mind. I find myself ignoring almost completely my reticle. Now, I'm not doing this on purpose of course, but maybe this has something to do with my almost trash aim?

I'm basically wondering if I should focus more on the enemy or my reticle. Also, any other aim tips are more than welcomed! (My DPS is 800, I don't think that's an issue.)