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Hi and welcome back, Cacophony Your reality checks should be as often as possible and not done in just a habitual mindset of 'Oh, i haven't done a reality check for a while..' Really make sure you question your reality as much as possible and follow it up with a reality check.
Personally, I try to do a constant RC through out the day. I don't use the normal methods of nose plug, finger check or anything like that anymore. I tend to try and focus on the feeling of the dream. Don't be discouraged if you don't have any lucids while you get back into the phase, though. Reality checks may take a little while to show up in your dreams

good luck!