This is how you can make script blocks appear in your game(s). This block should have a collider.

What materials do you need for this?

You really need just one. I recommend using the Stone half block.

How do you edit the block?

If you are using a stone half, you can just cut out one layer of the top, the front side, and the right side. If you are using larger blocks, you'll need to cut down more of the listed sides except for the right side. For the right side in this case, cut only one layer. For smaller blocks, you'll need to add layers. After that, "paint" the block so it looks like a script block.

How can this be tested?

Leave editor mode first. After you've left editor mode, click or press play, and not edit. Also make sure the level is the same level that you built the block on. If your synthetic block doesn't appear, you've used a script block.