The first thing one may consider can be using DIY carpet cleaning methods. It may feel a nice idea to use household products but they are not much effects on every stain.
For the best result it is best to go for a professional carpet cleaning company. I would suggest trying Back 2 New Carpet Cleaning Sydney.
They have the best and qualified team of cleaners to tackle with any of carpet related issues. They even use eco friendly methods so you will not have to worry about the chemical smell anymore!
I know many people are afraid of chemicals as they may do the harm to your so much loving carpet. But if you know the basics, you can be sure to do things right. Here is a guide I found on web and implemented few things - https://www.thevacuumbuddy.com/how-to-clean-carpet/ See what works for you as every scenario is different.
A good vacuum cleaner especially upright also helps cleaning carpets fast and deep.
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