For foreign currency futures it depends in what currency the contract size is quoted. If the contracts are quoted in $’s, then if the transaction involves buying $’s then we buy $ futures (and sell later). If the transaction involves selling $’s then we sell $ futures (and buy later).
For interest rate futures, if borrowing money then we sell futures (and buy later). If depositing money we buy futures (and sell later). (Although you cannot be asked calculations on interest rate futures in Paper FM).
I explain all of this, with examples, in my free lectures on foreign exchange risk management and interest rate risk management.