If you locate a rust spot on your vehicle, taking action to prevent it from spreading is your best course of action.  Start by scraping the rust off using a razor blade or fine grit sandpaper.  Be careful not to damage the paint surrounding the rust spot.  Only remove the rust, try to avoid scraping off the paint surrounding it. If the paint is flaking off, it means it is no longer bonded to the metal in that area and will likely fall off anyway.  If it is flaking off in a large area, you may need to have that portion of the vehicle repainted completely. Once you have scraped off the rust, apply an over the counter rust arrestor to the area.  This will prevent new rust from forming in the area.  Most rust arrestors come with an application brush; dip the brush in the rust arrestor and then apply a thin coat to the area that was previously rusty.  If your rust arrestor does not come with an application brush, use a Q-Tip or small rag to apply it to the metal.  Do not spray it on. You can purchase rust arrestor at most auto parts stores. Depending on the type of rust arrestor you choose and the environment, it may take up to a few hours for the rust arrestor to dry completely.  Read the instructions on the bottle to ensure you allow enough time for it to completely cure before moving on to the next step.  It may take longer for the rust arrestor to dry in cooler or more humid environments. Rust arrestor will dry faster in direct sunlight. Use a small applicator brush to apply automotive primer to the area that used to be rusty, over the dried rust arrestor.  The coat of primer should be thin but complete, so you can’t see any metal through it.  Make sure not to over apply the primer so it begins to drip.   Use a paper towel or rag to dab up any excess primer before it has the opportunity to drip. Allow the primer to dry completely before adding automotive paint. You can find the correct shade of touch up paint in a number of ways.  Many auto manufacturers can provide you with a bottle of touch up paint based on...

How would you rephrase that briefly using Indonesian?
Kikis karat dengan pisau silet atau ampelas kasar. Berikan penahan karat (rust arrestor) untuk mencegah penyebarannya. Biarkan penahan karat kering sepenuhnya. Berikan primer di atas lapisan penahan karat yang kering. Cari warna cat mobil yang sama dengan sebelumnya. Berikan cat perbaikan di atas primer.