Each online store has its own rules for making payments. Most of them have protection systems for the buyer such as AliExpress, Alibaba.com as well as specific ways to make purchases safely, but it is also important that you know some tips to buy in China safely.
Buying online, even with shipping, is usually cheaper than buying in local stores, but watch out, because that also shows in the quality, and a lot if you buy the cheapest.
To make payments you can use PayPal if the platform allows it (not all accept operations with this application). PayPal protects your card information, and has protection mechanisms in case you have not received the product or are unsatisfied.
Many of the Chinese stores have free or fairly low-cost shipping services, and the disadvantage of this is that the products you purchase this way will arrive within 15 to 25 days.
However, you can pay for shipping so that it arrives in a shorter time. Companies such as EMS, FEDEX, UPS, Servientrega and DHL can help you make your purchase arrive as soon as possible. Costs vary according to the weight of the product you have purchased.