The +/- 30 degrees is irrelevant to a racetrack. That only applies to a baseturn, 80/260 and 45/180 (the other three reversal procedures).
1. Fly straight to OEM for a direct entry, could descend to MSA before reaching OEM. Once passing OEM you can start descending to the platform altitude of 2500ft and enter the racetrack.
or..
Request to intercept QDM 183 for a straight in approach. You can descend to the IAF altitude once within the 25nm as it's above the MSA.
2. If coming from the south, but east of QDM 003, fly straight to OEM for a teardrop entry, where you can start descending to the platform altitude (2500ft), track 30 degrees off for 60-90 seconds (max 90sec) then turn right and continue outbound track 003 to 10dme, make a right turn and straight in.
If coming in from south, but west of QDM 003, fly straight to OEM for a parallel entry, where you can start descending to the platform altitude (2500ft), track outbound (track 003) parallel to the inbound track to 10dme, turn left to intercept the localiser inbound and go straight in. You cannot go below 2500ft until established inbound on the localiser. Only then can you descend to 2200ft which most likely will be just inside of the IF. You do NOT have to fly the whole circuit in a parallel entry unless being way too high for the final approach segment.