The easiest and most straightforward advice is: - Avoid cloud services - Avoid services that require an account - Avoid installing proprietary apps - Use Fr

The easiest and most straightforward advice is: - Avoid cloud services - Avoid services that require an account - Avoid installing proprietary apps - Use Free and open-source software (FOSS) if possible There are of course always situations in which it is unavoidable to do one of those mentioned not-to-do things, but if you stick to those simple rules most of the time, you should be able to avoid the bulk of the undesirable stuff out there.