I am developing a novel and have two main characters that start the story off separate but interacting with the same situations. I was wondering how often it would be OK to change between the two of them. At this point, I am switching every few pages after each of them interact with a situation. Will this be too jarring for the reader? This is my first story involving multiple main characters and I seem to be having problems keeping both of them as "main characters" instead of moving one of them into the background.
I would say that every few pages is too often. I have read books before where the narrator changes every chapter, which was fine, but it does take away from the relationship that the reader develops with the characters. So...I'd say every chapter, maximum.
Swapping POVs on scene boundaries can also be acceptable, but you need to be good at managing the transitions for it to work well. It's generally a bad idea to switch POVs within a scene, although I have seen rare occasions where it worked (Frank Herbert was capable of that).
I've seen it done several times within a chapter and I managed to keep it all straight, but I really don't recommend it and rarely do it myself. At most I'd change once in a single chapter, but I actually like having each chapter be the switching point (not every time of course, but if I'm gonna do it I'll make it then). It's easier on you as writer and on the reader too. Even if that makes a chapter painfully small or large at least it makes it an easier read and to me, in our world of short on time and even shorter attention spans, that's a good thing.
The only tid-bit I can add is that my professor tells me that it must be 'justifiable' when you switch. As in random switching without any particular importance can throw the reader off. Therefore, switching often... say every few pages, can be very awkward without a good and meaningful transition.
I have been changing the point of view after each scene (usually a few pages) to let the other character react to the scene. There is never a change mid scene as I know that as a reader it would be very hard to keep track of. Thanks for the tips, ill be careful about how I do that.
Check out William Faulkner's "As I Lay Dying" for a good example. I always thought he had a good method of switching points of view in a story. When you start a new point of view, you could start a new "chapter" with that character's name as the header, so the reader knows who is speaking. Just make sure the voices of each character are different from one another; if they're very similar or exactly the same, consider using just one point of view.
Okay, so you are switching your point of view every few scenes to give that character some time in the spotlight, and spread the characterization. This really depends on your goal within the story, whether you want a single main character to draw the reader's empathy, or multiple ones. It really depends widely based on the story. I agree that every chapter is the most you should do, even if this leads to shorter chapters. I know that's what I do when I write, at least, and I have read many other authors who do the same. Herbert messed me up the first time I read that, though I caught up quickly. However, I really wouldn't advise trying to write like him from the get go
I agree with most of what has been said above, and just wanted to add that when you're switching between characters, you might want to be careful and make sure you're not backtracking and just recaping scenes from a different point of view- unless you really think it's progressing the story somehow, like for the purposes of characterization or creating dramatic irony. However, it can be fun to leave the audience in the dark about a character's thoughts- I think it's a good technique that effectively emulates real life. Anyways, I'm rambling now. Good luck!