I don't think many people have the ability to alter their coin flipping technique to make one side or the other more likely. But even so, if you wanted to protect against this then don't learn the results, and that way the results cannot bias your flipping technique.
that's correct. that's only way to make sure.Quote
Two options for this. If you have someone you trust completely with your bitcoin (such as a spouse), then have them note the results from the flips for you, while you don't even look.
the only way i would accept that solution is if you hand over your completed private key and wallet details to your spouse once done. Quote
If you don't have someone you trust completely, then film the process using an airgapped device and watch the video back after you have made several hundred flips (on average with an unbiased coin you will need to make 512 flips to generate 128 bits of entropy).
correct. that's what i thought you might say. thats what i would have said. 