The flamenco Rumba is one of the most popular forms and also one of the simplest. Though many of the flamenco styles os palos are based on counting to 12m the Rumba is in 4/4. We count 1-2-3 1-2-3 1-2 with the 1 being accented. The first beta usually is accented with a golpe, the 4th beat is accented with the upstroke of the thumb, then beat 7 usually has some sort of percussion. Another way to count it is 1-2-3-4-5-6-7-8.
Flamenco guitar great Paco De Lucia popularised the Rumba with his hit Enter Dos Aguas which I use as an example in the video tutorial.
If you would like to delve further into the flamenco Rumba you can try my Rumba Strumming Course here