garble

1. To mix up or distort to such an extent as to make misleading or incomprehensible: She garbled all the historical facts.
2. To scramble (a signal or message), as by erroneous encoding or faulty transmission.
3. Archaic. To sort out; cull.
e.g.
The typesetter accidentally garbled the newspaper story, giving the reader only a mixed-up articles.
The company had garbled the bike's assembly instructions so badly that we were constantly confused about which step to do next.