What is the best cover up?

i cant find my shadeee!! its soo annoying i always buy one too dark or so my skin looks fake, i have tan skin. not black or dark, tan like olive skin but im not asian or anything like that. and after wearing cover up 1 time the next day i have more zits, i do wash my face morning and night, im not that stupid. the cover up/foundation i use is liquid so that might be why. the brand i use is cover girl tru blend. whats a good cover up/foundation? and do i have to use a powder cover up? please helpp