I'd get an RFP bribe and/or do RFP jobs until you can get RM jobs.
Alternativley you can get bribes for all the Rheinland factions which tends to send your RM rep sky high. Get double bribes if possible, i recommend New Berlin
What? RM reps isn't that hard. You just go to a BS and keep taking RM missions until your rep is maxed, be advised that bribing other Rheinland factions will make things faster, you may very well accidentally get the wrong IFF instead.
Unless things have changed with the new version, acquiring RM rep is a piece of cake. Just do RM missions straight from creation (favour missions against Hessians, as it's the fastest way). Also pay attention not to pick up BHG missions rather than RM, as there are (used to be) BHG missions from RM battleships.
I suggest doing (we usually do) missions in the Dresden system, from the battleship there. Pick missions close to the battleship (sector 4C?). Doing that, sometimes the battleship will help you finish the mission. Problem is that those missions are random, so you may have to keep relogging and trying for a long time before one apears.
Bottom line:
1. Do missions for the RM straight away;
2. Do not take missions for anyone else (including the BHG missions offered at the battleships);
3. Prefer missions against Hessians, not only is it faster, it's also guaranteed that your RM reputation will rise faster than other RH lawfuls, preventing you from acquiring say, Kruger.
Assuming things have not changed much since the last mod, my preferred location for RM missions was the Westfallen. From here, one could take missions that were a mere 20k run into the Kielfield (if that). Also, as most of the missions were against Unioners, and Unioners have so few enemies, it was incredibly easy to guard tag...all I had to do was drop RFP, Rheinland corps and RM.
Awesome help. i thank you all for the tips. I see now that the people that was telling me this stuff have no idea what they were talking about. Maybe it was hard for them because they're lazy and do not want to take the time to take and do the missions.