This DIY bookmark pen tutorial shows you how to make a unique accessory that works as both a bookmark and a pen — with perforated tear-off bookmark pages wrapped around a standard pen ink cartridge. Every time you tear off a bookmark, there is a fresh one underneath, and the pen is always right where you need it inside your planner or book.
It slides into any planner, journal or book like a regular bookmark, but with a pen cartridge hidden inside so you can write immediately without hunting for something to write with.
Here's the whole build in under a minute:
The build takes about an hour once you have the materials, and makes six bookmark pens from a single sheet. It's a good first project if you've never used a perforating cutter — the cuts are all straight lines, so there's nothing fiddly to get wrong.
New to planner making? Start with our complete guide to creating custom planners.
What You'll Need
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You'll also need double-sided tape and six pen ink cartridges — either buy the cartridges on their own, or take them out of six cheap pens.
A note on the cardstock: 220gsm is the sweet spot. Lighter paper won't hold the cartridge firmly and the bookmark goes floppy after a few tears. Much heavier and the perforations won't tear cleanly.
Get the template
You'll need the bookmark pen template to print. Open it in Planify Pro to change the size, colours or design before printing — or use it exactly as it is.
Export and print
In Planify Pro, go to Save/Export → Selected Page → Paper → A4, then click Generate PDF.
Open the PDF in Adobe Acrobat Reader to print at 100% scale. This matters more than usual here — if the printer scales the page even slightly, the 3.5cm columns won't line up with the cartridges and the whole strip will be out by a few millimetres.
Instructions
1. Print the template on cardstock. Check the printed width against a ruler before going further — the columns should measure exactly 3.5cm.
2. Fold the sheet in half. Crease it firmly — this fold becomes the spine that holds each cartridge, so a soft fold means a loose bookmark.
3. On the back, draw a vertical line every 3.5cm. You should end up with six columns — one per bookmark pen. Use a ruler and pencil, since these lines guide both the tape and the perforations.
4. Apply double-sided tape along the top edge. This seals the folded sheet closed once the cartridges are in.
5. Apply tape along each drawn line. Keep it just to one side of the pencil line rather than straight over it — the line itself needs to stay clear for the perforating cutter.
This is how the finished tape placement should look — one strip along the top and one beside each column line.
6. Score each vertical line with the perforating cutter. One firm pass is enough. Going over the same line twice tends to cut clean through instead of perforating, and then the bookmark falls out on its own.
7. Get six ink cartridges ready. Pulling them from cheap ballpoints is usually cheaper than buying refills, and any standard cartridge works as long as they're all the same length.
8. Place a cartridge into each column and make a small hole at the bottom for the tip to poke through. Push the tip through before taping anything down — it's much harder to adjust afterwards.
9. Secure each cartridge with a small piece of tape so it can't slide up and down inside its column. All six should sit parallel, with the writing tips level along the bottom edge.
10. Peel the backing off the tape and fold the two halves together. Press along each column so the tape grips either side of every cartridge.
11. Bend each perforated section back and forth a few times. This softens the perforation so the bookmark tears away cleanly rather than dragging the next one with it.
12. Snip a small triangle from the top and bottom of each perforation. These notches give the tear somewhere to start, which is the difference between a clean pull and a ragged edge.
That's it — six bookmark pens from one sheet. Tear one off, use it until the ink runs out, and the next is waiting underneath.
Troubleshooting
The perforations tear too easily. The cutter went over the line more than once, or the cardstock is too light. One pass on 220gsm is right.
The bookmark won't tear cleanly. Bend the section a few more times, and check the notches at top and bottom are actually cut through.
The cartridge slides around. The tape either side isn't gripping. Open it up, add a strip closer to the cartridge, and press firmly along its whole length.
The columns don't line up with the cartridges. Almost always a printer scaling problem — reprint at 100% and measure before assembling.
Selling these
Bookmark pens work well as a low-price add-on product. They're small, cheap to post, and unusual enough to stand out in a shop full of planners — which makes them a good impulse buy alongside something larger.
They also bundle naturally. A notepad, a set of planner inserts and a bookmark pen makes a gift set worth more than the sum of its parts, and the pen costs pennies to add.
If you're selling the finished item rather than the template, price for assembly time as well as materials — six pens is roughly an hour of work once you're practised.
See 20 profitable planner niches and easy templates that sell for more product ideas.
What You Need to Get Started
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