Repeated practice
If you want to talk eloquently, it is essential to practice repeatedly. You can face the wall, pick up a long article and practice it repeatedly until you blurt it out.
Dabble in all kinds of books
Being involved in all kinds of books can make your eloquence more comfortable. The wider you dabble in, the more handy you will be.
Writing and eloquence
Writing and eloquence are both important, but each has its own advantages. Excellent writing proves that you have deep attainments in a certain field; And eloquent, you need to be knowledgeable and have something in your words.
Logic and expression
If you think the writing is not good, maybe the logic and expression need to be strengthened. You can read more famous works, such as Lu Xun, Bing Xin and Lao She, and learn how they capture details and make the language more attractive.
Patience and persistence
Practice eloquence, not in a day. Patience and persistence are the key. Don't expect to advance by leaps and bounds in two or three days.