Yeast has a sour smell. That means your flora is off. Shower using tea tree oil soap. Don't take tub baths. Avoid eating sugar and grains, which turn to sugar. Take a probiotic daily, which is kept in the refrigerator. Don't get a cheap one. Eat organic vegetables and fruit and yogurt. Use fresh herbs when cooking. Things like garlic and oregano and tea tree oil are nature's cure for yeast (don't take tea tree oil internally). If odor is fishy, that would be bacterial vaginosis, and needs a doctor's prescription.
When you're on your period, make sure you change tampon or pad regularly. When not on period, keep it clean. Shower regularly. I wouldn't use douchy or anything as its scented . Same with the perfume, don't do that. It ends up throwing off the pH balance and can cause it to smell more or create an infection. Your vagina cleans itself. I also would make sure not to use fabric softeners or detergents that are really perfumey for your underwear. Vaginas have a natural smell from person to person. If you feel like yours is abnormal, see a doctor so they can do a pap test.