Talk to your doctor, and ask to be screened for all common cancers. A colonoscopy is in your future (I just had one). Also ask for a Prostate-Specific Antigen (PSA) Test. Also look into the HPV vaccine.
Don't do this. Nearly all cancer tests are overly sensitive, and not great at detecting the cancers you care about (the ones that will progress).
If you run out and get a bunch of random cancer tests, you are basically ensuring that you will get unnecessary and painful treatment for a finding that probably wouldn't have harmed you in the first place.
It's not a satisfying answer, but it's true. The reason most cancers are found late is because there's no effective alternative.
HPV vaccine has to be the biggest bang for buck. To anyone reading this, you should get it at any age because you likely haven't been exposed to all the strains that e.g. Gardasil-9 protects you from. You should also get it if you're male despite it being initially known as the cervical cancer vaccine because HPV causes oral cancers and you also don't want to potentially be a carrier.
