This guide is very long, I didnt cover everything I suggest going to this link http://smashboards.com/showthread.php?t=142180 this is a very good quickie guide. thanks for the comments looks good! :)
Standard Move Set
First move we going to cover is his standard B move. This basically just pulls Pikmin out of the ground, it does no damage and has no use for battle, used best when enemy dies or is off the level to restock. Make sure to have 6 at ALL TIMES. I can't stress that enough, he uses them as a basis for everything he does and you really need 6. If you have less say goodbye to his recovery and his Up B move is severely weakened.
Next will be B down. If you've ever played the game Pikmin, it does a little rainbow sweral around your character. To a new player you might be like wtf is this for? Well its to call his Pikmin back immedity. I personally done use it very often unless I see my self flying off level, always always always use before you try to latch on side when trying to get back on, if you don't one of your Pikmin might be "out of range" to help the team latch on, so using this will immedity bring him into range and give you that little extra distance he might need.
Next move is Over and B. This move is very interesting and use-full when used correctly. I will be going through what each Pikmin does when thrown basically showing how good each is and when to use this move. But beyond that the basic move is, you throw a Pikmin it latches on and attacks the enemy. If he does nothing if will continue for a long time racking up good damage. The enemy will have to puck kick do something and it will instantly knock the Pikmin off. Another good tidbit you can have more then one Pikmin on a character at once time thus doubling damage, very use-full when playing a defensive game.
Up B, this move is frankly downright amazing. If not the hardest to master and control move in the ENTIRE game. It does OK damage at 6% (when both characters at 0% 0%) but the real beauty of this move is the fact if your enemy is flying upwards and you have confidence you can hit them, they can go flying even higher and they have ZERO chance to hit you back. If you have 6 Pikmin and you use this move you have a HUGE range advantage against the person flying off screen. Biggest downfall is how hard it is to hit as its a small area. Master this move before going to a tourney with Olimar and you should see you wrecking people easy.
Learning what his Pikmin Do.
Each Pikmin of a different color mostly has a type element. So let me run through the basics of each of his different Pikmin.
Yellow You can tell by guessing what most type of the element is by just the color, this is yellow so we go with electric. The yellow Pikmin are good for throwing as they do a decent 16% (the numbers I ran with were full durations of the Pikmin being on the enemy and only 1 as you can have more then one Pikmin on a character, but this is just a rough number to show how good/bad it is overall) When its on an enemy it does a OK 2% damage per "tick" (thats the term I use for Pikmin latching on and attacking) The yellow Pikmin have an ok range while throwing as its medium weight. Overall yellow are good when in air for using his up A and down A attacks, very nice splash damage if you can hit an enemy overall good Pikmin to use no downfall. Blue I will come out and say Blue, Yellow and Red are the same, everything I said for yellow apply for Blue and Red. Biggest difference is, Blue is not Elemental and just hits the enemy. He has same size as Yellow and does 2% tick per hit. Overall no down-falls like yellow. Red Again Red has same properties like yellow, but is fire, overall good splash damage. Purple Finally I can show how different some of his Pikmin can be. Purple is by far the fattest and by this the "hardest" to throw. It has short range, and no elemental damage. If your enemy has a high % damage and you throw one of these guys so goodbye. He is pure knock back and little damage. (he does 5%) Also be away he can NOT latch on and do tick damage. He is more or less a projectile of knocking. Overall good for using in your smash attacks, and can give you little extra knock just enough to kill the other character earlier than you might be used to. White Here is the best Pikmin for throwing by FAR. he does 4% per tick. And if he stays on for full duration he does 48% really great. Get 2 of these bad boys one 1 character and say hello to easy damage. He is the lightest so you can throw him the furthest by far, so watch you don't throw him over edge. He does purple poison and is mediocre for anything else besides throwing. His smashes are ok, but weaker then yellow, red blue, but overall you'll want at-lest one in your arsenal for throwing. Everything Else I didn't cover
So here we are almost at the end of my little guide. I will cover some more things fast so lets do this quick as my hands are starting to fall off.
Olimars grabs are ranged as he uses Pikmin to run over and grab, very good at throwing your enemy a curve ball. Again each Pikmin does different Elemental and this will happen also in your grab so beware of that also.
ALL of his smashes are ranged as he send a Pikmin flying, be aware that elemental will again come into play, and his smashes is really where he shines, he has low defense but if you can use his Pikmin right you shouldn't have a problem keeping an enemy from hitting you. Pikmin are your key to winning so always pay attention to how many you have and I can't stress learn to Micro-manage.
Learn to LOVE his down A smash. It spreads out in all directions, and has a GREAT range. It has pretty good knock, and this is something a lot of people don't know. You can use this as a shield against projectiles. If someone throws something and you use this, the Pikmin will take the hit and leave you standing with 0% damage. VERY VERY USEFULL. Remember this and learn to time it correctly against different projectiles. Just another reason why you shouldn't be getting touched.
Heres a good tip I learned for seeing the order of his Pikmin. Just jump, it spreads them out and you can see clearing what is coming up next. Might be annoying to do in heat of battle but when your alone on level easiest and quickest way.
Beyond that just learn his dodges and stuff like that you should be golden for 1v1. Heres another quick Rundown
All attacks are range
OK speed, but enough to keep you out of harms way
Lots of Variety
Up B best in game * this is based on knock ability and the enemy literally having no defense against it*
Requires a great player to Micro-mange his Pikmin
Needs to be mastered to become a power house
His recovery isn't always the greatest.
Lucas can outrange and go THROUGH Pikmin thus hitting you. PLAY DEFENSIVE against this character.
So there you have it, a quick guide or really a long guide. But whatever hope you enjoyed. Give me some feedback. If you would like another character throwing it up in comments and I will see what I can do. I don't always main everyone but I do play everyone to learn everyones move set and how to defeat them. So thanks again! :)