No, we wouldn't say that. The expression you are looking for is 'to try your best'. You should try your best at all times.

No, we wouldn't say that. Actually persisten isn't a word. We would most likely say, "Please keep persisting (through)". We don't usually put persist and effort together. Although you could probably say, "Thank you for your persistent efforts".

please make persisten efforts = por favor, de hacer esfuerzos persistentes Yo nesito hacer esfuerzos persistentes I need to make persistent efforts ellos nesesitan hacer esfuerzos persistentes They need to make persistent efforts