Because of minimum age rules, I just spell out the number if I can't recycle the old password yet.
One of the reasons I don't do IT security any more is the attachment to old dogma like these kinds of password rules by auditors - they are the real barrier to making policies more effective.
I never wrote my password on a post-it on my screen. The post-it had tallies of the number of times I'd incremented the number at the start, and the number at the end.
And I worked on my IT department, and then went over their heads, until they got smart about password expiration.
At my previous role I added a number and kept increasing until it accepted the orginal password and I started the cycle again.