I recommend 2 steps:
Step 1 - Paint protection.
As others have mentioned, apply your preferred type of paint protection asap and keep applying it as recommended by the manufacturer. Some, like StealthP3D above, like the carnauaba waxes. If you go this route, I also recommend the Collinite family of waxes. They are very durable. However, if you have any PPF on your car, they may not be PPF safe. A few months ago, I had contacted Collinite to ask if their waxes were PPF safe and they said in reply that they are "in the process of testing on PPF and their safety for PPF has not been determined yet".
I personally have shifted away from the traditional carnauaba waxes and have been using ceramic-infused spray sealants. My new favorite is The Last Coat 2. I also like and recommend OptiCoat Hyper Seal and Turtle Wax Hybrid Ceramic Spray Wax. These spray sealants are much easier and faster to apply than traditional carnauba waxes and they are much more durable and last longer between applications. Most importantly, you can use them on all exterior surfaces, including black trim, glass, and chrome. Not only will they not get white stains or smudges on your black trim, they will actually protect them and keep the black trim from fading.
If you want to go for the most and longest lasting protection, you can consider PPF and /or ceramic coatings. They are amazing but do cost $$$.
Step 2 - Washing
Once your car has adequate paint protection applied, the key to keeping it clean is to wash it frequently and not let the dust/dirt build up. I will do a traditional wash maybe once every 6 months. I mainly do rinseless washes (using ONR) or waterless washes about once a week. As long as you do not have caked on dirt, waterless washes are quick, easy, and effective. But you do have to use proper technique to avoid scratching the paint. BTW, another advantage of a PPF-covered car is that you do not have to be as careful when doing a waterless wash. Since PPF is self-healing, any scratches or swirls just disappear after about 20 minutes in the heat of the sun.
In addition to ONR for rinseless washes, I have used and recommend these waterless washes:
Meguiar's® Rinse Free Express Wash & Wax, D11501, 1 Gallon, Liquid | Meguiar's
McKee's 37 Waterless Wash On The Go Concentrate makes several gallons of ready to use waterless car wash!
But remember, both of these waterless washes contain waxes and/or gloss enhancers. So do NOT use them if you are about to apply a wax or sealant. You don't want any waxes or gloss enhancers on the paint before applying a wax or sealant, as they will prevent proper bonding to the paint. For washing just prior to applying a sealant or wax, I would suggest either a traditional wash using something like Meguiars Gold Class Car Wash Shampoo or, if you want to go rinseless, Mckees37 n914:
N-914 Rinseless Wash, D-114, D114