If you don't have spot gold in your hand, but you are ready to buy it, but you are temporarily short of funds, you can buy futures gold in the futures market. Futures is a margin transaction, and you only need 10% of the total amount you need to buy to complete the transaction, which is equivalent to the contract margin. So when you have enough money in the future, you can buy the gold you need in the spot market and close your position in the futures market. If the price goes up, you buy it in cash, but the futures also go up, so you can make money, so that the futures profit can make up for the high spot purchase, ensure your purchase cost, and revitalize the funds at the same time.

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Go ahead. If you are a gold merchant and have spot gold in your hand, you can sell futures in the futures market if you are worried that the price of gold will fall. When the spot fell almost, someone bought it and closed the position after delivery on the futures. In this way, although you sell low in the spot, you are profitable because you sell high and buy low in the futures (the futures price follows the spot, so it also falls). Futures profits make up for the part of the profits that stocks are sold less. It can be said that you sold them at a high price.

As can be seen from the above, futures provide a tool to avoid the risk of spot price fluctuation, so that you can operate with peace of mind without worrying about future price fluctuations. Pay attention to buying hedging if you are worried about rising prices, and selling (futures) if you are worried about lowering prices. The number of futures trading should be basically the same as the number of risks you need to avoid in the spot.

Supplementary answer: the example process is as above, but there are specific data.