1. spend less, to then have spare money you didnt have before to accumulate
2. invest in legit investments that accumulate interest/deflationary margin
3. work more hours
4. ask for pay rise
5. get second job
6. find some tax deductions
7.any other dependants in your house get another job, promotion, more hours to increase household income
8. rent a room to a stranger
9. sell good or services(hobby/side hustle on ebay/garage sale/fiverr/facebook market place/etc)
10. start a business
I think all you mention are the only ways an individual will make money, as it is now in the world, because all you mention are the keys to making money, especially the second and fifth ones. I really support them because investing in a legit platform and getting a second job will definitely help an individual accumulate more money and spend less on other things that are not necessary in his life or things that cannot positively impact his life.
Although the 7th one, I can say it will depend on the type of location you find yourself in. If you leave a location where there is no job or maybe in your house, you are the only person who has enough knowledge or a certificate to qualify for a job. You can see that another person in the house will depend on you after getting the job, although they can also have another skilled job to help them earn some money.
There are many legitimate ways to earn money without resorting to the ones you mentioned that can bring you a good monthly collection.
The ones the OP mentions are not even enough, or, let me say, are not a legit source of income in my opinion, because I didn't make much sense in what the OP mentions. How can we use those methods he mentions? Another example is this forum. You can earn in this forum if you are knowledgeable about bitcoin and the discussions that take place on the forum. Someone can use the knowledge they have about bitcoin and cryptocurrency to get signature campaigns on the forum and start earning money weekly. That is also another source of income using your knowledge since you must first learn.