“What is the best way to improve my lactation naturally?”

The body will produce supply when there is a demand. A lactation consolation might be in order. They are very helpful and usually have a couple of recommendations

Here are a couple of options that have been very useful for many women, and I’ve even used myself: Mother’s Milk tea by Traditional Medicinals is a great daily addition to support healthy lactation and supply, and making lactation cookies or brownies can help too! I have some examples here below, but if you use another recipe you find online, make sure they include whole oats, flax seeds, and brewers yeast which is great for boosting milk supply.
Also, make sure you are WELL hydrated, and eating enough makes a positive difference in milk supply. (Not drinking enough *water* is a common reason for the low milk amount produced. Poor diet quality or not eating enough commonly leads to poor milk quality.) Finally, keep in mind that if you’re stressing out a lot over this or overly stressed in general, that can also have a negative effect on lactation.
https://www.medela.us/breastfeeding/articles/oatmeal-chocolate-chip-lactation-cookie-recipe
https://www.sugarandsoul.co/lactation-brownies/

Sesame juice

Drug free. No Pseudoephedrine.

Find a skillful naturopathic doctor in your area.

Milk production is most affected by the frequency of suckling and the hydration status of the mother. However, milk composition varies according the mother's diet, reflecting her dietary intake.

You could try slow cooked oatmeal, fennel can be cooked with or made into a tea as can fenugreek, blessed thistle, milk thistle, or nettle.