One of the hardest things for writers to do is to hand their work over to others to be critiqued. No one wants to hear the bad stuff. It's hard, after all of the time and effort that you put in, to hear that something doesn't work or isn't right. But, truth be told, it's the bad stuff that will make you grow. Sure, it's nice to hear the compliments (and yes, those are important too), but it's the constructive criticism that will make you rework your story to be better.
Critique partners are an essential part of the writing process. They can help you see things you can't about your story, they can help give you suggestions when you get blocked, and they can help motivate you to stick to deadlines, which is ridiculously important if you hope to ever finish whatever it is you are working on. So many benefits – but it's essential to recognize that not everyone would make a good critique partner. So how do you pick a critique partner? What qualities are most important? Well here are a few things to consider:
Find someone whose opinions you trust. Perhaps this person is an avid reader or even a fan of cinema, which makes them familiar with storytelling. Either way they should be familiar with the elements of good storytelling.
Find someone who will be honest with you. (Remember, we aren't looking for someone to just blow smoke up our bums – we need to hear the harsh, honest truth.) Ideally it will be sandwiched between some awesome positivity and encouraging reinforcement, but sometimes it isn't and that's okay.
Respect that everyone's opinion may differ. What someone dislikes may be someone else's favorite part, but it's important to hear what parts stand out to certain people and why.
Find someone who adheres to deadlines and routine. It's okay if things come up. That's life. (As long as they keep lines of communication open and let you know that something has delayed them.) But generally speaking, if you are exchanging work and your partner is consistently late or unable to produce a critique, that is no bueno and pretty unfair, if you ask me. You want someone reliable. As much as you may be friends, remember that this is still supposed to be a professional working relationship.
You do not need to write in the same genre in order to be critique partners. Though they may not know the tropes and conventions of your genre in particular (and vice versa), they still can help you identify issues that are common to all stories, maybe character development or inconsistencies or perhaps issues with plot holes. Actually, an outsider's perspective can offer some interesting suggestions that may be delightfully divergent from your genres norm (aka clichés).
Now two VERY important things to remember once you find a partner (or partners) to work with:
No matter who is critiquing your work, be it a friend, a writing partner, or a big wig New York agent, at the end of the day, this is your story. Take the recommendations, or don’t take them. In all honesty, the choice is up to you. And I say that with the utmost sincerity. You are the artist and only you know what you envision for this story and its future. Critics can give their suggestions on how they would say the story/plot/characters can become stronger, but the choice is all your own. Surely, they are not the be all, end off of all things literary. No one is. At the end of it all, they are readers, just like the rest of the general public will one day be. And ideally you should know and trust that your critics' recommendations come from a place of respect and honesty; they should want to make your story the best that it can be. If in your heart of hearts you feel that this is not their greatest motivation, then maybe they aren't the best critique partner for you.
One of the greatest mistakes writers experience is that they can take the criticism personally. Generally (especially if you find the right partner), no one is attacking you. Everything that is being said is for your benefit and your growth. I've witnessed (more times than I can count) people lose their poo in a critique session. High tension, blood pressure rising, balled fists, hate-fire in their eyes. Yikes. Trust me, some things are hard to hear, but there is no reason to become hostile. If you feel that a critique partner is being too harsh in how they present their criticism, then take a breath (and a day or two to cool off) and then address it calmly and professionally. Maybe they are doing it without even realizing it. Long story short, constructive criticism is not a personal attack and the second you see it as such is when you aren't getting the most of the learning experience that it should be.