If you're not a HNWI I wouldn't bother buying individual bonds (and if you are, you're probably paying someone to do it for you). You can get 99% of the benefit of this full ladder just using a few etfs. Check out $VGSH, $VGIT, $VGLT - expense ratios are only 0.07. But also if you're young you probably shouldn't worry about this. You don't hold many bonds anyway and you shouldn't be trying to time the market - just buy a total bond fund and forget it.

If however, you do want some pizzazz in your bonds, also check out barbells and bullets. The concept is the same as a ladder except you're not equal-weighted across time. And then check out Vanguard's short, intermediate and long corporate bonds and you can do similar things in the corporate space.