You can do your best to avoid it by making sure none of those paints are off due to age, I'm sure the guy you got them off didn't buy them the day before he retired, but old or not it is wise to strain them before puting them in your brush, these measures won't guarantee no clogs ever but will certainly expand the time it takes to happen.
Once you have all your equipment be sure to hit us up for advice on everything, there is plenty to read here but your questions are more than wellcome and very likely the quickest way to get advice.