At times I can speak English fluently enough. The biggest issue bothering me is that when not carefully speaking, I mix 'he' and 'she' pronouns randomly. Example: "Jane's not here today. He's on a holiday."
When writing, I don't have this problem. The reason for this issue is that my native language has only gender-neutral pronouns so my brain is not wired for this kind of thing.
The question is: How to teach myself to use 'he' and 'she' automatically correctly when speaking?