The only and best tip is follow good nutrition. Use zinc related multi vitamin minerals. Eat more protein food. This helps grow thick hair.
Monthly once eyebrows shaping is really a good idea. I prefer to use a pencil. Powders can look very dense, and while that might look great for the runway or an editorial in a magazine, it looks very harsh and severe in real life.
Using a pencil lets you draw little, feathery strokes that look more like hair.