We can go far with idiomatic English even if we are not native English speakers.
Using idioms is building bridges to where we would like to be. We would like to close all communication gaps, wouldn't we?
Communication is not just about speech. It is also about how we present ourselves. Our postures matter. So, a standing mirror helps. With a handy smartphone recording our practice, meanwhile, we can always play it back and have a better idea of how we are doing. Isn't self-teaching wonderful?
As for our accents, don't take them as liabilities. They can be exotically charming. Who knows? We'll be okay as long as we keep ourselves open to communication which, by the way, is a two-way street.