Stix,
The only way I can suggest to help is do it the way I do, and that is set yourself a target you want to win on the day and stop.
In my case $400, but I nearly always finish up with more because of overs.
Some days the overs are very good say $650 up for the day, and if I feel like having a play around after getting my wages I will use a $100 and have $10 bets. The interesting thing about this is more often than not I will blow the $100 so just shows how my average day would pan out if I kept my normal size bet.
The only other way I can think of is to marry a filipina like I have and believe me you can't stop betting quick enough as there are more interesting things to do.