Sample Representativeness

#1
Hi guys,

I am doing analysis on a sample to figure out the sentiment of a population.
In my data I have various demographics of the respondents and their rating indicating their satisfaction with a company. I want to make sure the sample is representative of my population. For this I plan to do a chi square test on the various strata (demographic variables). My problem is choosing the strata. Is there any statistical way of choosing which strata should be representative in order to figure out whether my sample ratings are as close as possible to the population ?

Thanks in advance.