There’s not an exact time that we can recommend, as all babies are unique and it will depend on how tired baby was, how much sleep they got that day, etc. Ou recommendation is to be sure baby falls fully asleep. You can also try working on your bedtime routine if baby is waking up fussy—white noise and dim the lights 20 min before bedtime. bath time, etc.
There’s also no need to institute a regimented cry-it-out plan if what you’re currently doing is working for your family. But good sleep habits never hurt, and being able to fall asleep on one’s own is a necessary life skill. If you sleep-train at a time that’s developmentally appropriate for your baby and with the basic ingredients of healthy sleep in place, you can minimize the amount of crying your baby (and, let’s face it, you) will do.