Don't wait for others to reach out to you. If you feel you're a good reviewer, just hit up all the major review sites and offer them your service. Have a sample of your work, describe your usual methodology etc.
If that doesn't work, start your own blog ie with top ICO picks of the month, share the content on this forum (dedicated thread), Steemit + on social media. If you get any traction, you could start charging ICOs for featuring them.
Get this advise which is exactly true and was suppose to say the same thing.I would say that theres no need to be professional because even basic steps would really be sufficient enough for you start of.
If you do know on what are your strengths then seek out for those review sites and might consider your service.