A little while later the rate had drifted up to 0.8355 and suddenly started to tick up quite rapidly. I stepped in and strongly encouraged she close position when the rate hit 0.8359, creating a $180 loss for the trade. DW still thought I'd panicked, but although the rate did drop back a little bit at various times in the next hour, it was definitely trending up rather than down.
After DW went to bed I stayed up watching the cricket world cup (Australia vs. NZ) and noticed that an up trend now seemed well established - so I went long at 0.8366. After continuing upwards to around 0.8370/72 the uptrend ran out of steam and I thought about closing the position for a small gain ($30), but left the position open as I was still watching the cricket and could check on the price every ad break. Eventually DW got up during the night to change DS2's nappy, and we watched the up trend resume. Eventually we got tired (Australia had NZ on the ropes at 7 for 140 or thereabouts, with NZ chasing 349, so the cricket had also lost interest), so we closed the position at 0.8372/74 for a reasonable $80 profit and went to bed.
So far our forex trades have a 75% success rate, but not sticking to the $100 stop loss limit was an expensive lesson for DW. Of course 4 trades are not indicative of any trading skill or lack thereof - once we've clocked up 100 trades we'll be able to see if we have a statistically significant deviation from the roughly 50:50 win:loss ratio you'd expect from random outcomes (actually, you'd expect to "win" less than 50% of the time, as CMC Markets is taking a $20 cut of of each round trip).
I believe that "successful" traders (allegedly exhibiting skill rather than luck) typically achieve around 65% winning trades, with their profitability depending largely on letting the winning trades run, and cutting losses ruthlessly according to a set trading plan. We'll see how things work out. Anyhow, with a $1000 starting stake, and now a $300 or so "buffer" to cover margins, DW should be able to have some fun trading before she runs out of margin and has to call it quits.
Trading so far (1% margin on $100,000 AUD/USD spot price)
Trade Capital Open Close Profit
Short (SELL AUD) AUD$1000 0.8369 0.8362 US $70
Short (SELL AUD) AUD$1000 0.8328 0.8296 US $320
Short (SELL AUD) AUD$1000 0.8341 0.8359 US-$180
Long (BUY AUD) AUD$1000 0.8366 0.8374 US $80
Overall US $290 (AUD$346.23 CR)