How do employees select the right employer?

employer has to select the one who satisfies his needs

you can check the terms and condition in the contract,if it satisfies u, you can also get the details of organisation , talk with some existing employees, it will help u lot.

I believe it depends on the organization's culture, the value of the organization and benefits & services.

Every employee has his own needs and requirements - like salary, bonuses, increments schedual and other benefits. If employer fulfill all the requirements of the employee, so he got the right employer. 

its long process , but the more core point is to select your candidate in competency based process from A - Z