To move a block, move your cursor over its title bar. The cursor icon should change to a crosshair. Now just click and drag the block to where you want it to be moved to. A thick dotted orange line will appear where the block is going to move to. Once this line appears just release your mouse button and the block is moved instantly.
Tip: You can move a block to a different page by dragging it into the Block Clipboard sidebar, navigating to the destination page and dragging the block to the desired location.
Tip: If you hold down the Control key while dragging the block out of the Block Clipboard, a copy of the block remains in the Block Clipboard. This is handy when you need to copy the same block to multiple pages.