It's funny to me how my hobby has actually helped me do things at my work (mostly using digest-sized booklets for training documents). Today the job gives back. These aren't earthshaking, but two things you can do with your house rule booklets:
If you want a visual way to indicate sections in a booklet the simplest way I've come up with is to use different color paper. Works best if you can break your booklet into 3 sections. Make sure the middle section is an even number of pages. Now, just print 2 booklets, one in color A and one in Color B and swap the middle sections.
Say you've got a booklet for players running down class abilities-- Fighter, Cleric, Magic-user, and you want the sections visually distinct. You've got goldenrod paper and white. Print a goldenrod booklet and a white booklet. Then swap out the middle section and you've got one booklet with a goldenrod cleric section and one goldenrod booklet with a white cleric section.
If the former is what you really wanted you can keep the latter for yourself or just discard. A waste of paper, but unless your printer handles back to back printing well (mine jams every time) and you want to carefully count out colored paper sandwiches for it, it's the only practical way I've come up with to do this.
QR codes are a fancy bar code that you can scan with your phone to take you right to a web page. If you have a physical document in your hands there might be few reasons to have an easy link back to the digital realm, but I can think of two.
You might want to save precious space in your booklet by offloading less important information onto a webpage. Names are a good example, I think. During character creation some people have no problem coming up with an imaginary name others are stumped and slow down everything. You could tell them "scan that code" and have it link to a page with a list of names. Like this one:
The codes are supposed to be able to encode text in the 1000 character range, which got me excited with the possibilities (think solo adventures, private notes, an alternative way to do this). But again when I tried encoding small paragraphs the codes wouldn't scan. Maybe I was doing something wrong and that's still a possibility.
note: After typing this up I found out Christian apparently has used qr codes like this in Loviatar. I hadn't seen that, though, so maybe you hadn't either.
I just realized you can scan the codes off a screen! So, if you're a
DM that's using a tablet or notebook a lot having players scan a code
off your screen might be faster than emailing or texting a link. This
all assumes a bunch of technology and I'd rather just have simple paper
tools, but as a DIYer I'm also open to all possibilities.
Okay, If you've got booklet tips please share them in the comments.