Odor is caused by bacteria, so in order to get rid of the odor you have to get rid of the bacteria.
Bacteria love four things - warmth, moisture, darkness and food. Given all of those they will grow like crazy. The more of those you remove, the less bacteria you'll have. We can't do much about the darkness unless you want to walk around nude all the time. The warmth is also difficult to remove. About the only thing you can do is wear boxers instead of briefs. They allow air to circulate down there and keep you a little cooler. That leaves us with the moisture and food.
Food for bacteria is your dead skin cells that you normally shed. This is where frequent washing comes in. Soap works by removing skin oil which traps the bacteria in, so you want to make sure you use plenty.
Finally there's moisture which comes from your sweat. Keeping the area dry is key. After washing make sure you dry yourself off well, especially the area between your scrotum and legs. Powders help absorb moisture but can also be irritating. Baby powder is ground talc which is a stone. Arm and Hammer is baking soda which is less irritating. There are powders made just for this, just look in the drug store for powders made for "jock itch." It's also important to wash the powder off as soon as it becomes saturated so it doesn't cake up and hold the bacteria in.
The areas bacteria love most are between your scrotum and legs and under your foreskin (if you have one). Pay particular attention to them when washing, but don't put powder under your foreskin.
Keep this routine and you should see an improvement.
thanx so much um what about baby oil
Baby oil is OK as a moisturizer on your shaft, but don't use it on the areas where you get this rash. BTW, baby oil is nothing more than mineral oil with fragrance added, so if you don't want the "baby" smell you can get mineral oil, which is odorless, in the drug store.