Well I'm fairly suprised that one of these hasn't been posted yet.
Basically you can post your deck(s) and give the strategy for it possibly have it rated, etc. Please make sure that you play by the rules actually and don't submit a charizard ex and call it a deck.
Anyway, to show you how it's done, I'll start with my deck.
Dark Energy: 6 basic and 3 special for a total of nine dark energy cards
Grass Energy: 15 basic
TOTAL ENERGY: 24
Premier Ball(Great Encounters): 2
Prof. Elm's Training Method(Dragon Frontiers): 2
Bebe's Search(Mysterious Treasures): 2
Amulet Coin(Great Encouters): 2
Holon Mentor(Dragon Frontiers): 1
Master Ball(Delta Species): 1
TOTAL TRAINERS: 10
Darkrai(G/E,3/106): 1 (There are two different kinds of darkrai in this series so this is 3/106)
Darkrai LV. X(G/E): 1
Treeko(EX Dragon): 1
Grovyle(Ruby and Sapphire): 1
Cacnea(Crystal Guardians): 4
TOTAL POKEMON: 26
Ok so I have plenty of energy in my deck to support the attack cost of my pokemon. I don't want to run out ever so I keep a little less than 25 energy in my decks usually.
I have my trainers there which most are supporter cards just so I can keep geting the cards I need quickly, as most decks do.
Now for the best part. I have four Zangoose because they're basic and fairly strong for something you can just throw out there since you only need one energy to attack with 20 damage. Zangoose helps me since he can take a few hits while I play a trainer or evolve a pokemon on the bench.
Treecko is there so I can evolve him and I would use him as a last resort since cacnea can call out a basic pokemon from the deck(darkrai). Once Treecko evolves he gets tough. Really tough in some situations where I don't even need to evolve him anymore. Sceptile is final and can really kick some ass even though I've never gotten to use him yet.
Cacnea can call for family which lets me take a basic pokemon from my deck, as I said before. Once he evolves into cacturne though he's sometimes unstoppable. I like to take advantage of needle arm's effect.
Finally, Darkrai. The first one I mentioned is sorta crap unless you're fighting cresselia or are planning on leveling him up immediately. The Other Darkrais though can actully KO pokemon fairly easily and are my preference to level up into Darkrai LV. X. Once he's lv X he's just incredible. He has yet to be seen destroyed.
So that's a basic, pretty mediocre description. If you don't understand what attacks are/do/etc, please use this site. It has scans of almost every card made.
So if you have some time try to get some posted!! And Don't forget to give your opinoin on other's!