Dear Miss Della,
thank you so much for this little modification of my suggestion in how to cum!
(Now, I'm glad and thankful for this

)
Here a slightly late report of my great release:
Monday evening I had enough undisturbed time to do it.
I put the shoelace on the table and after undressing I begun to tenderly squeeze my cock at the base.
It took much more time than expected to get to a full erection. Perhaps, I was too afraid and nervous about my own task.
I tied my balls nice and firm into an exposed little package. It felt really good.
As you said I started by slapping my balls 5 times. I did them not really painful and hard, but hard enough to be close to the limit of being slightly painful. And I enjoyed each one!

The following 10 strokes felt great, but it was way too less!
So I increased to 10 slaps and 20 strokes. A little bit better! The slaps still felt nice and the strokes, too!
I increased to 15 slaps and 30 strokes. It was getting different: The slaps felt still good, but at the end a nice tension and a slight pain filled my balls. The following strokes have been a good alternation.
I went on this way and with these slaps my cock became more and more flaccid each interval. That stroking was more and more targeted to come back to full erection.
This changed a bit with the larger numbers and my cock was really hard and sensitive when I finished the strokes.
Finally after the interval of 85 slaps and about 130 strokes an awesome orgasm brought the release I was looking for!
It was such a great feeling!
(OMG, I just summed up: 765 slaps and about 1500 strokes!)
Later I had a good night without too much pain in my balls. Hmm, I expected more.
But during the next day a nice dragging pain in my balls have been present and I loved that feeling!
Thank you for helping me with this new experience!
Regards
selfbound