Select the blocks that you want to align.
One of the selected blocks displays empty selection handles, like the Constant block in the figure. This block is the reference for aligning the other selected blocks. If you want to use another block as the alignment reference, click it.
From the Diagram > Arrange menu, select an alignment, distribution, or sizing option. For example, select Align Top to align the top edges of the selected blocks with the top edge of the reference block.