Sidescan help?

So, I'm fairly new to nicer finders, definitely a bit of a learning curve. Loving sidescan,  especially for finding  out if there are schools of kokes and rockfish about. However, I don't know how to discern how far off to the side the suspended schools of fish that I see on the finder are...
Any info would be a great help, and very appreciated!

I'm in the same boat... My understanding at this point is
(1) You know how far away the target is from your transducer
(2) If you're picking up the bottom on the same side as your target, and the target is casting a shadow on the bottom, you can sorta guestimate how far from the bottom your target is (shadow is close to target means it's close to the bottom).
(3) Some sort of trigonometry involving [water depth], [target distance from transducer], [estimated depth of target].

But honestly so far I've only used my sidescan to target suspended schools of bait for vertical jigging... My process usually involves a series of 90 degree turns and straight lines until I stumble my way on top of the bait.

So, I did some figuring out whilst on the salt today.
A big school of rockfish appeared on the sidescan, and I immediately made a 90° turn in that direction, traveled only maybe 10-20', before I saw them on sonar. I hope this helps others.

the best way to figure this out is in your settings (garmin, lowrance etc) will have a zoom feature on the side scan telling you how far you are looking... once you have that sorted out you need to understand the depth of the water you are fishing in and what frequency you are running your transducer at... for example the rule of thumb for higher frequency (200khz) would be that the diameter of your cone is 1/3 the depth you are fishing in at the bottom... low frequency 77-90khz is generally going to give you a cone that is the same diameter as the depth you are fishing in....

or...

you can just mark the return you are seeing in your side scan with a waypoint and then navigate to it with you sonar on...