Being a resident pilot in Munich, my best advice for you would be to catch a scheduled flight. Nowhere else in the civilised world are conditions for GA pilots worse than here. If you absolutely have to, then here's some additional information:
Oberpfaffenhofen (EDMO) is available (also IFR) PPR with a MTOW above 2000 kg, see
Willkommen am Sonderflughafen Oberpfaffenhofen
Fürstenfeldbruck is also PPR and VFR only, see
FFB Fürstenfeldbruck Flugbetriebsgesellschaft mbH (ETSF) . It may close soon.
Oberschleissheim is PPR and VFR only, see
Flugplatz Schleissheim e.V. - Startseite . Very good connections to public transport to downtown Munich (S-Bahn), but they only have a limited number of operations available to non-based aircraft which may have been exhausted by now.
EDMD, Dachau-Gröbenried, is a gliding site with 425m grass and is PPR (and from what I hear it's difficult to get one).
Otherwise, there's Jesenwang (EDMJ), but its 408m narrow runway with a forest at one end is not everybody's cup of tea; see
Flug- und Freizeitzentrum Jesenwang.
Erding (ETSE) is military and I think off-limits to civil aircraft other than the ones based there with the military flying club.