Magath, who led Schalke to a second place finish last term in what was his first season at the club, has seen fan support erode quickly through poor results and a number of controversial winter transfers.
"I need this support but the team needs this support as well," Magath said in a four-minute video on his new Facebook page, which boasted 20,000 friends after just one day.
"I am here because of the fans and the emotions, to go together with the fans to try and win the (Bundesliga) title and bring it to Gelsenkirchen."
Schalke are among the best supported clubs in Germany but are without a German title since 1958. When 32-year-old Iranian Ali Karimi and 30-year-old Greek striker Angelos Charisteas were brought in at the end of January some fans warned they were in danger of being turned into a "senior citizens' team".
Schalke are 11th in the Bundesliga, 25 points off the top, but are still in the Champions League round of 16 after cruising through the group stage.
"It will be difficult against clubs who have much more money than us and that is why I know we can only do it with you, together," said Magath, who has coached Bayern Munich and VfL Wolfsburg to Bundesliga titles.
Schalke take on Freiburg on Saturday.
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