This is probably really something you should learn to do yourself. Doing opacity maps is not difficult and you don't have to be a great drawer.
Im not sure what it is you don't know what to do, I'm guessing its 2D editing so here is how.
Step 1
you need a 2D editor. I mostly use paint dot net because its easy to use and is free.
Step 2
You need to show iClone where your 2D editor is. Here is how to do that

Step 3
Then you can send an objects images to your 2D editor for editing it
Here is how to send the Opacity map for editing. You can also do this with the other objects images too

Step 4.
When completed the editing of the image just save it to automatically update the object in iClone
Here is an example of the result

OK, those methods work fine when its easy to tell where to paint things on the image so they appear in the correct place on the object your adjusting.
When its not so easy to tell where to paint things so it appears correctly on the object you should use the method of doing it with UV map
Step 1
Send the UV map to the 2D editor
Here is how to do that

Step 2
You cant save and automatically update the object in iClone when doing it this way. You need to save the image to your computer and then load it into the objects texture manually.
Here is how to do that

If this is not what you don't understand the you need to very specifically explain what it is you don't understand. Then people know what to answer with
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