Your accent is information about you, not a fault.

Being understood and sounding local are two different goals, and only one of them matters.

Everyone has an accent, including the people who think they do not. An accent tells other people something true: where you grew up, what languages live in your mouth, what roads you took to get here. There is nothing to fix in that. The useful goal is being understood, and being understood is mostly about things that have nothing to do with sounding local. It is about speaking at a steady pace, finishing your words instead of trailing off, putting stress on the important syllable, and being loud enough for the room.

When people say they were not understood, the cause is very often volume or speed rather than pronunciation. Nervous speakers get quiet and quick at the same time, and quiet quick speech is hard to follow in any accent. Slowing slightly and lifting your voice fixes more misunderstandings than months of chasing particular sounds. It also makes you sound more certain, which changes how people respond to you.

There is one small pronunciation habit worth having, and it is not about your accent at all. If a particular word of yours regularly causes confusion, learn where the stress sits in it and put it there firmly. English listeners lean heavily on stress to recognise words. Get the beat right and the rest can sound however it sounds.