Reddit mentions of Mindful Beads: 20 inspiring ideas for stringing and personalizing your own mala and prayer beads, plus their meanings

Not to add to the pointless debate that's ensued, "rosary" is a word associated with a specific religion. The term "prayer beads" is more commonly used in regards to all and non-Christian religions. It's an umbrella term, the rosary is one type of prayer beads. Just like the mala (used in Hindu & Buddhist practices) is another type. There is no universal format, each style of prayer beads differs from one religion/culture to the next. Personally, I think it is better not to use the term "rosary" as it is most closely associated with Catholicism/Christianity and Neopaganism already has enough borrowed baggage due to Christianity's general influence on society. "Prayer beads" conveys what the object is and without confusion or debate.

If you're not adhering to a tradition, then the number and layout of prayer beads would be whatever is significant to you. A couple of books that could help you get some ideas are "Mindful Beads" by Alice Peck and "Pagan Prayer Beads" by John Michael Greer & Clare Vaughn. A search on any bookseller site, Amazon or otherwise, will likely produce several other titles.