How do I improve myself in NORMAL games?

Do you constantly battle in situations in which you are unsure if you can beat your enemy, or do you play purely to win? If I am fighting a and I'm unsure if I should fight him, do I test my limits for further use or do I simply play safe and wait until I can surely beat him? Of course this is a normal game so losing doesn't matter and it may help to test my limits, but I might lose out on some other aspects of winning just because I fed a because I was testing my limits.

What do I do?