I once demonstrated a trade procedure for a friend who was new in trading bitcoins. All i did to make the trade successful was to introduce him with localbitcoins traders in our region. And he said that was cool after successfully trading.
Trading online is not safe 100% so every trade that is made online has it own level of risk and it own process until it gets finished, for bitcoin it is good when the buyer goes first so the seller is a little more protected that the buyer will not make any chargeback like in paypal.