Ask someone who hires to review your portfolio

You can easily find people who are willing to spend time mentoring you on the website ADPlist. There you can filter the mentors by job titles to find only those who might have hired service designers in the past. For example:

1. Get mentored by Heads of Service Design
2. Get mentored by Service Design Leads

Sites where you can ask for portfolio reviews

Below you'll find websites where you can send your portfolio and get back a critique of your portfolio (in no particular order). These websites focus on UX portfolios but the feedback can still be helpful.

1. Marie Shaw (99$)
2. Ian Fenn (99$)
3. UXplaybook (99$)
4. Scott La Counte ($70)
5. The Designer Toolbox (99$)

Public portfolio reviews

I have added for you a few public portfolio reviews. These reviews are of UX portfolios, but there are still lessons to learn.