Your simplest never failing memory place: your body. Let the loci (locations) be, and let’s follow this route:
But, you can go beyond just your body and select much, much more loci for the body. Assuming you only use these 32 loci, if you select 50 people, you’ll have 1600 very quick. At least for me it is easy to visualize a person’s body and you won’t confuse yourself, because you’ll have more than one marker on them to distinguish them. Face, height, weight, clothes…
Example of prospect bodies, altough people you’ve interacted with you may find very easy to imagine:
Gal Gadot - Wonder Woman
Use the portal method by placing your “people” in a proper memory palace, take loci and assign them.
How it is this more benefitial than using a place you’ve been to or a photo or video or an artificial place? Well, it is about the speed of selection of loci and route (Memory Journey), if you define 32 for your body or more, that same map can be traverse in another body. Again you won’t be confused because you, won’t be seeing the same “places”. For instances, each of the images uploaded, if you see them as they are, with those clothes, you can’t possibly confuse yourself, and the simples visualization of then will give you a memory palace. Here is when similarities don’t confuse but speed up the process.