I've just one thing to add, to explain the grammatical differences between the words suggested here. 'Improve' is both transitive and intransitive. eg 'A touch of salt will improve this soup' (transitive) 'My French has improved a lot' (intransitive) 'Get better' is only intransitive. 'He took some Chinese herbs and his health immediately got better.' 'Make better' is only transitive. 'These Chinese herbs will make you better.'

And, on top of these options it is also okay to use the verb "to better". E.g. "To better oneself" is a phrase that means to make yourself a better person, by learning something new or perhaps by being more honest. Tom

"To make better" is a good option.

The right word is "improve" but you also can say "get better" for informal conversation.