I’d say, make a low poly basemesh, that has the shape (silhouette) you want and then you can make a duplicate and sculpt on that, so you can later bake the sculpted details on the (UV map of the) low poly version.
Or, if you use the Multiresolution Modifier to sculpt the details, you could Bake from Multires…but I’ve never done that and would even then save a low poly copy, just to be sure.
