Looking for advice to improve my WvW gameplay.

Well, I'm not a complete moron. I've been playing GW1 and GW2 for years (Mesmer main), albeit mostly PvE. About 4 months ago I decided to get into WvW, chose a Shiro/Glint Herald (sinve Rev was the only class I hadn't played yet) and it was shocking how much I sucked at first.

I am 90% roaming and I have improved a lot since then (at least my k/d ratio confirms that), mostly when it comes to using my skills effecitively and not just spamming them, positioning and general movement. Even my sustain has gotten better. In the beginning not killing an enemy quickly meant I was about to die.

But I often notice how much I focus on myself and how little attention I am paying to what my enemy is doing. I obviously dodge red circles, try to dodge/evade/block obvious attacks, but in general my skills when it comes to REACTING are pretty poor. Doesn't help I'm playing on a potato pc with all graphics settings set to low.

Long story short, can anybody give me advice or maybe share some epiphanies they had to improve in WvW/PvP?