Hello!
The clues at the bottom are "horizontal", they deal with things being next to one another (or not) and the ones on the right are "vertical" they deal with things being in the same column. It's a convention from the original Sherlock, but it is sort of arbitrary, so maybe it's not needed!
I've added a comment above giving a more thorough explanation of the rules - I should have included this from the start, so it's no wonder everyone is a bit confused by it. Hopefully it's a bit easier to understand now :)
Thanks for playing!