Why are you getting angry at plates?
Are you referring to mild frustration or actual anger?
I don't get angry in general anymore, if I do it literally never lasts more than a few seconds. However, I'm prone to frustration when I feel people are violating my expectations and not acting the way I think they ought to -- subconscious judgement and disdain on my part, among other things.
I am a regular meditator and practice mindfulness throughout the day, so I can usually notice when thought patterns of frustration or anger begin to arise within me, and just by bringing awareness to the thoughts and feelings associated with these emotions (versus unconsciously identifying with them), they lose their grip and power over me... and as a result I don't experience those states for long at all.
I recommend cognitive behavioural therapy (CBT) to understand your own perspective, and how you can reshape your beliefs about the situations that cause negative emotion in you. You don't necessarily need to see a therapist, but if you learn the ABC technique and apply it to your own life it can be helpful.
I also recommend starting a mindfulness and meditation practice if you haven't already.
You're always going to have your mind with you in every situation you ever will encounter, so why not train it? Train yourself to insert awareness between stimulus and response, to develop the ability to recognize when your attention redirects to negative thought patterns and to be able to be mindful when the associated physical sensations that accompany such emotion are affecting your body.
So I recommend CBT, mindfulness, and meditation to manage your anger towards your plates.