This is for beginners or people who can't quite build a well-rounded deck.
Step 1:Select a theme. There are many different themes to base your deck on. Two theme that I see most often are XYZ decks and Six Samurai decks.
Some themes aren't so specific, like Dragon decks or Zombie Decks. My favorite theme is a Custom Themed deck. Custom themes are themes that you can personalize.
Step 2:Gather Themed Cards. If you have the necessary cards, skip this step. If there is a theme you absolutely desire but you don't have the cards need for it(i.e. you want XYZ but you don't have Z-Metal Tank), the best way to get the cards is by trading. Hoping that they appear in a pack requires some luck.
Step 3:Assemble. Now that you have the cards, it's time to build the deck. After all the themed cards are in your deck, you can add cards that you think will go well with the deck.
Step 4:Test. Test your brand new deck against your friend, family member, or anyone who is willing to play you.
Challenging Themes:
A-Z Theme:You must have at least one card for every letter in the alphabet(i.e. you might start with Alligator's Sword and End with Z-Metal Tank).
3 Star Theme:All monster's in your deck have to be level 3 or lower.
All Monster Theme:No spells or traps are allowed in your deck.
All Spell and Trap Deck:No Monsters are allowed in your deck.
Good Luck!