It depends on the type of gravy I am making what I do. For turkey or roast beef gravy, try using corn starch instad of flour. Mix it with a little cold water before you slowly add it to the bubbling broth. Stir constantly until it is well mixed. You can adjust the thickness by the amount of cornstarch you use. If it thickens too much,add a little water or broth,stirring as you add it. This makes a rather clear looking gravy.
For fried chicken or what I call white gravy, stir flour into a little grease in the skillet or pan. I have always used Crisco to fry chicken.(Do not use oil to make gravy.It won't work) Let the mixture brown and stir til smooth. Add milk or water a little at a time til it is the thickness you want.
I followed what my mother did and it has always worked for me.
Lois