another newbie with questions about trading tennis

Hello,

I've been trying to make money from gambling (using betfair) for ages now and have barely broken-even, so I've moved over to trading. Despite my best efforts with gambling, my emotions always got the better of me (lack of confidence, chasing etc), and as I can program I thought that if I wrote a bot for trading that would remove a lot of the up and down problems I had with gambling.

I trade the tennis for small ticks but I wondering just how cautious I'm being because my profit over the match is seldom more than 10% and the vast, majority of my trades end up as scratch trades. Is this 10% a laughable amount? (please laugh quietly if it is...) I know this is a how-long-is-a-piece-of-string-question, but how many trades does the average one-tick trader place during a tennis match, and how much profit would you expect to make?

Also, do you always close one trade before starting the next? Do you submit both back and lay bets at the same time?

thanks - apologies if these are stupid questions

I know someone who was doing binaries for F1 and football on IG Index (also works with Binary Bet). I think he waits until towards the end when it's almost certain but not quite and keeps an eye on the race/penalties/etc so it's around 80% and bets per point that it reaches 100%. I guess you just have to be quick to bail if things go unexpectedly as there is no stoploss.

I don't have a TV so cannot confirm if this works or not or if it'd work for tennis...