See the slide below. A weave effect shows how vertical and horizontal things are interconnected (in this case stuff I did back at McKinsey). It is impossible to weave shapes in programs such as PowerPoint or Keynote, they cannot be on top in one spot, and at the bottom in another,.
One way to get around this is the visual trick I applied here. Stick to a flat grid of boxes and colour/connect them to fake the visual effect. Super easy to make, super easy to change (adding, removing rows and columns). Below is the basic grid structure I used for this chart:
In PowerPoint and Keynote it can still be fiddly to line up all the boxes, especially when you want to make changes to a grid. You might have to resort to tables with very fat white margins between cells,. In SlideMagic it is super easy and even fun to create these charts. (Pro tip: SlideMagic converts to PowerPoint and can do the hard work for you).
I have added a variant of the slide to the SlideMagic template database (find it here, or simply search for “weave” in the desktop app)