The only instructions for installing any nonfree program including Flash is:
1. Do whatever the developers tell you to do.
2. Hope what you did works and doesn't break your system.
3. Be subjugated by the nonfree software. Hope that the software doesn't do
more subjugation than you expected.
Nobody on this forum is going to help with this process of subjugation. The
most any of us are going to do is help the person who made the mistake of
going through this process remove the nonfree software.
If nonfree software is absolutely needed (you should check first, try some
solutions), then a distro that includes nonfree software is probably going to
be better for your needs than a free system like Trisquel anyway.
