Answer first
Use one minoxidil product at a time: Folli-Fix or Folli-Fix X10, not both, and not with another brand's minoxidil. Stacking increases the amount on your skin and the chance of irritation or side effects such as dizziness, without a clear benefit.
Pick one
Your consultant can help you decide between foam and liquid.
Other leave-ons
Ask before adding serums like Folli-Flux to the same area, and space them out.
Questions
Can I switch from Fix to X10?
Men can, after advice. Don't overlap them.
What about oral minoxidil?
That is a prescription medicine; talk to your doctor and don't combine on your own.