The answer to this question is very simple. You need to be creative and think outside the box.
First, you can create some content that will benefit your customers by writing blog posts, ebooks or anything else that will help them solve their problems faster. This way you can make money even if you are not doing any work.
You can also start a service business like running a website design company where people can hire you for your expertise in web designing services. And when it comes time to pay for these services, there is no need to worry because many of these companies accept payment through Paypal and other online payment platforms which means no cash transactions required!
If this was not enough then I would suggest you try creating an app which could be downloaded from the Google Play Store or Apple App Store and earn revenue from advertisements displayed on the app itself or from in-app purchases made by users of the app. The more downloads your app gets, the more revenue it generates which means making money while you sleep!
Hope this answers your question!