Quote from cabletrader:
Calculate risk not the leverage you use, for example....
Account Balance: $100,000
Risk: 2% - $2000.00
Eur/Usd Sell @ 1.2575
Stop Loss @ 1.2625
$2,000 divided by your 50 pips stop loss = $40 per pip = 400,000 trade size
-or-
Account Balance: $100,000
Risk: 1% - $1,000.00
Eur/Usd Sell @ 1.2575
Stop Loss @ 1.2595
$1000 divided by your 20 pips stop loss = $50 per pip = 500,000 trade size
-or-
Account Balance: $100,000
Risk: 5% - $5000.00
Eur/Usd Sell @ 1.2575
Stop Loss @ 1.2585
$5000 divided by your 10 pips stop loss = $500 per pip = 5,000,000 trade size
etc etc etc....just adjust trade size according to the risk you're prepared to take and the stop loss of the individual trade.
Nowhere did you need to work out your leverage, it doesn't matter.