If the first digits after the comma are zeros, the number is to be pronounced like 'the integer part + (запятая) ноль ноль .... + non-zero digits one after another'.
1,01 один ноль один
1,005 один ноль ноль пять
5,00084 пять запятая ноль ноль ноль восемь четыре
If there are three or more the same digits one after another, they may be pronounced like 'три нуля', 'восемь троек', 'четыре девятки'.
1,00043444177777 один запятая три нуля четыре три три четвёрки один пять семёрок
So if it is difficult for you to remember all these rules, pronounce decimals like 'the integer part + запятая + the digits one after another'. It will not sound natural always, but everyone will easily understand you, it will not be a big mistake and probably it will not be a mistake whatever