Napoleon's Army, the Civil Service exams in China, and, previously, America; it seems things thrive when they are rewarded for effort. What might it look like if we rewarded people for political effort? I don't really know, but I'll throw out some ideas.
Learning the language of your current country is pretty much required, as a first step? To enter the infantry of your country's democracy you would need to be able to find out what is going on. To read is, perhaps, the next step, because the serious ideas are all written down. I could never be convinced that someone who received their news only from the American radio or television news services knew very much. Of course, some people could be told about the government, the different jobs of the different elected offices, without reading about it, and someone else could learn to read and only ever read movie star gossip.
Fuller participation involves writing and public speaking, knowing more details about what the government does, about the different departments, and about the laws and elected officials currently in place.
All these things seem like they could add up to form a "merit score" for a citizen in a democracy. Perhaps certain offices would only be voted on by people with a suitably high score. Similarly, particularly low merit might be a bar to seeking certain offices.