I don't tend to go close range because it's so easy to leave yourself vulnerable. Sometimes leaving yourself open once is just enough for your opponent to get the better of you. My main strategies are different depending on the weight of my character.
Light Characters: Since light characters are usually easy to send flying, I prefer to take it slowly, only attacking when the opponent leaves themselves open.
Medium Characters: I prefer to fight in a position that is close enough to hit, but far away enough to steer clear of powerful attacks, which usually don't have a great range. If the character is like Samus, then I use a projectile to stun them, then rush in and strike as fast as possible, not giving them a chance to attack.
Heavy Characters: With these I just think, aww, to hell with it and go for a close range attack frenzy. Since heavy characters aren't very easy to send flying, I just charge in and take them out fast.
Well, those are my strategies. Except for the heavyweight strategy, my strategies rely on avoiding as much damage as possible while dealing as much as possible.