in understanding when to buy or sell future which is buy looking at either the contract size or the variation in the spot rate. Could you provide an example where we buy futures
You need to look at what currency the contract size is quoted in.
Suppose the contract size is in $’s, then if the transaction involves the need to buy $’s then we buy futures. If the transaction involves selling $’s then we sell futures.
Have you watched my free lectures on this where I do explain the ‘rule’ ?