what do you check for before you open a buy/sell trade?

I usually check the spread of the instrument to be sure the broker has not increased it. I then check that I am about to trade the right instrument because sometimes i can have many charts open at the same time and could erroneously trade a wrong instrument.

@Paul this almost happened to me today. I was on GBP/USD chart instead of EUR/USD and I almost placed a trade on it but i cross checked and found out i was on the wrong chart.

I check the spread of the currency pair I am about to trade. If the spread is higher than what I was expecting, i will leave the pair.

Strategy wise, I make sure the pair has presented my trade opportunity before I click a buy or a sell.