I've been trying BLW but my son is more interested in throwing food on the floor than putting it in his mouth! Can I do a mix of purees and finger foods?

Before 1 year old, your child's main source of nutrients is still from milk - so there's no rush to get LO to be eating solids yet! In fact, you can make sure that he is ready first - common signs are that he is eager to have food and can sit by himself unsupported. When he is ready, offer foods slowly and patiently - some BLW babies are able to start eating soon after they start, but most don't really "eat" until months later! BLW sometimes include many food throwing, messy clean-ups and figuring out what your child likes/dislikes. Most BLW parents may advise against doing a mix because it may cause confusion between whether he should be chewing or just swallowing the food (hence increasing risk of choking) - but it's up to your comfort level I guess!