user20994: So I've been able to combine two different clips shot by two different cameras at different angles at the same time by creating Multicam clip and choose to sync by sound. 
However, when I try to edit this multicam clip, it seems that I could only choose to show one camera clip at a time. I want my two clips to show side by side, like

I know to do that in a normally created project, we can just put two clips together in the timeline and edit transformations for both clips from "Transform" in here

But how can I do the similar thing to a multicam clip?
Maybe from here? (Seems that in here I can only choose to switch between angles at different timeline but not show both angels at the same time)

Thanks guys!

user20675: That’s not what Multicam clips are for, quite the opposite. Multicam clips are designed for showing only one angle out of multiple source angles. 
Did you try an synchronized clip instead? When the synchronization is done you can double click the clip and transform the individual clips to fit your screen. 

user25722: What you need to do is mark the edit points for the clip where you want the effect to appear. Then highlight the edited clip so that it is highlighted in yellow.
Now copy that clip by pressing Command+C.
Now menu over the clip and select “Lift from storyline”.
You will now have an empty grey clip on the Storyline.
Click on that Grey clip and paste the copy of the original clip on to it.
Go back to the start of the clip and then change the angle of the clip on the storyline.
Finally, change the size of the two clips to give the side by side effect.
Dependent on you snap options you may need to drag the clips back together to the right places, when you paste the duplicated clip onto the stroryline.

20994: <p>So I've been able to combine two different clips shot by two different cameras at different angles at the same time by creating Multicam clip and choose to sync by sound. </p>

<p>However, when I try to edit this multicam clip, it seems that I could only choose to show one camera clip at a time. <strong>I want my two clips to show side by side, like</strong></p>

<p><a href="https://i.stack.imgur.com/lwkk1.jpg" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/lwkk1.jpg" alt="enter image description here"></a></p>

<p>I know to do that in a normally created project, we can just put two clips together in the timeline and edit transformations for both clips from "Transform" in here</p>

<p><a href="https://i.stack.imgur.com/ZRa7c.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/ZRa7c.png" alt="enter image description here"></a></p>

<p>But how can I do the similar thing to a multicam clip?</p>

<p>Maybe from here? (Seems that in here I can only choose to switch between angles at different timeline but not show both angels at the same time)
<a href="https://i.stack.imgur.com/UPNgy.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/UPNgy.png" alt="enter image description here"></a></p>

<p>Thanks guys!</p>
 20675: <p>That’s not what Multicam clips are for, quite the opposite. Multicam clips are designed for showing only one angle out of multiple source angles. 
Did you try an synchronized clip instead? When the synchronization is done you can double click the clip and transform the individual clips to fit your screen. </p>
 25722: <p>What you need to do is mark the edit points for the clip where you want the effect to appear. Then highlight the edited clip so that it is highlighted in yellow.<br>
Now copy that clip by pressing <kbd>Command</kbd>+<kbd>C</kbd>.</p>

<p>Now menu over the clip and select “Lift from storyline”.</p>

<p>You will now have an empty grey clip on the Storyline.</p>

<p>Click on that Grey clip and paste the copy of the original clip on to it.
Go back to the start of the clip and then change the angle of the clip on the storyline.</p>

<p>Finally, change the size of the two clips to give the side by side effect.
Dependent on you snap options you may need to drag the clips back together to the right places, when you paste the duplicated clip onto the stroryline.</p>
