Migrate Collections from Manual to Automated

[TLB-joseph]

The collections on my website are a bit of a mess. I have a mix of manual collections and automated collections and over time tagging has got more complex, which has resulted in products showing in incorrect collections. 

I want to streamline the collections on our site to all be automated and edit our tags. 

Is anyone aware of a process that could help me streamline the process, or do I simply have to work my through my products and review tagging, then do the same for collections from A-Z and manually update/duplicate where necessary? 

Thanks. 

[TLB-joseph]

Anyone got any suggestions?