Can you give me your best tips for growing rosemary?

Rosemary need to be watered often. Touch the soil and water as soon as you feel the top soil getting dry. There are basically two ways to kill a plant. Over water or Under water it.

I keep mine on the kitchen windowsill. Most herbs like a sunny spot. Give it a little sun and keep the soil moist.

Mine are in ground and grow like crazy and thrive on neglect. Gowing in pots i is a little bit harder, and must be watered often and have well draining soil. See if these help you.

https://homeguides.sfgate.com/grow-rosemary-container-39314.html

https://youtu.be/zU_13zUtd90

https://www.gardeningknowhow.com/edible/herbs/rosemary/rosemary-grown-in-containers.htm

I am not a good gardener and I live in Maine which makes growing things more difficult so I have lots of pot plants. One is a nice healthy rosemary. I just water it and take it outside in summer. Try growing it in a pot, which allows for more flexibility in where you place it.

I'd say you are over watering and it is not getting enuf full sun. Rosemary grows everywhere here in AZ(it's used as shrubs in median strips on the streets) it needs full hot sun and drought tolerant conditions...water thoroughly between completely drying, needs good drainage, not a cold hardy plant, if young keep soil a little more watered to get it established, Rosemary thrives on neglect and poor soil. I have huge one in same lrg clay pot over 15yrs. They do not like moved or transplanting.Are you growing outside in ground?outside in container? which type are you growing(several varieties)? where do you live?city/climate?( this is world wide site)Are you trying to grow indoors?

If you are in zone 5 or colder grow it in a large pot and bring it indoors over the winter.