You can still try to find small and smart domain names for your website but if not available then try smaller and smarter domain as possible. For example you want to make a website regarding tooth brushes and the domain "toothbrush" is already reserved then you can try following "toothbrushes" "alltoothbrushes" "toothbrushes4all" "toothbrushstore" "brandedtoothbrushes" "brush2smaile".
But if all possible smaller domains are also reserved then registered then try long or longer domain but with dashes to separate keywords.