You know why you need an editor, and you know more-or-less what level of editing you need. Now how do you find an editor? Editors can seem elusive, but there are tons of us out there! Once you find some editors, you need to shop around a bit to make sure you find the right one. And I don't mean shopping only for prices.
Finding an Editor
If you're a social person, you can likely find an editor by going to local writing groups and/or book clubs. If there are no editors in attendance, people there should be able to recommend you to someone or tell you where to go from there.
If you're more likely to look online, there are plenty of places to find qualified professional editors. For one, you can find editors on social media. Look up the hashtag #AmEditing or #WritingCommunity on Twitter, and you will find a community willing to help you out.
A more direct way to find editors is through editing organizations. For example, I belong to Editors Canada. Many places have local organizations, so try Googling "[your city] editors" and see what pops up. These organizations generally have job boards where you can browse editors by subject or skill level. These are some well-known editing organizations:
If you are a member of the Alliance of Independent Authors, you can also find an editor through their online directory of vetted professionals.
Finding the Right Editor
Once you have some editors in mind, you need to find the right editor for you. You wouldn't want a technical editor doing a developmental edit on your historical fiction novel because they wouldn't have the right skills to perform that edit (and they likely wouldn't accept the job anyway).
So what makes an editor a good fit for your project?
They have experience editing your genre. Many fiction editors will edit across multiple genres, but few editors will have experience editing all across the board. Most editors specialize in a certain area, like how I specialize in editing fantasy and romance.
They edit at the level you need. Just as editors specialize in different genres, they also specialize in different editing levels. I specialize in copyediting and proofreading, whereas other editors specialize in developmental editing or book coaching.
They are interested in your manuscript. It is in both your best interest and the editor's if they actually want to edit your manuscript. They should show enthusiasm and interest in your work.
They are available to edit. Often, editors will book their schedules months in advance. If you know you'll need an editor in the coming months, start looking now. Also, keep in mind that the editing process could take months, so prepare to do revisions and collaborate with your editor over time.
They are friendly and get along with you. You may be working with the same editor for months or even years, so you need to make sure you get along with that person and trust them. Getting to know someone over email can be difficult, so if you'd like a more personal interaction, ask to discuss your project over the phone or request a Zoom meeting. Communication is key in editing.
Once you find an editor who meets your criteria, you should be good to go!
Many people also consider their budget as a factor in finding an editor, and although that is valid, remember that it may be worth paying more to find someone who will care about your work as much as you do and who has the proper skillset to work on your manuscript.