First of all, I want to say that I am not claiming to be the best deckbuilder out there. There are many people who have a better knack for finding the most efficient route to victory. Personally, I focus on the creativity that deckbuilding allows. I like to find weird combos with underused cards that make netdeckers scratch their heads and yank them out of "autoplay" mode.
I will say that I have made hundreds of decks at this point and I can confidently say that I have learned a thing or two. This article is for both newbies who are entering the game (welcome!) and for more seasoned players who might be interested in a view into another deckbuilders mindset and processes. Let's get started:
Find Your Goal: Every deck should have a plan to victory and every piece should play a role into completing that mission. Including a card simply because it is good in another deck is almost never the way to go. There are staples (more on that later), but you need to focus on efficiently completing a strategy that will assure a victory.
Leader and Super Combos: I put these together for a reason. Look at the leader that you want to build with and try to figure out what the natural strategy is. Masked Saiyan is far better at aggro than Zamasu. Androids play a much better midrange while most Friezas are control leaders. This leads into what kind of super combos you should run. A leader with Burst should almost always run a Sparking super combo while a self-awakening leader should almost always run a more traditional "4/5 life or less" super combo. Consider the type of deck you would like to play with this Leader. A slower stall deck would most likely benefit from a Sparking super combo while an aggressive deck would benefit from a traditional super combo. Android 16, Shugesh, Mighty Mask, and (to a lesser extent) Pan are special super combos that can be used for more creative strategies.
Finishing Turn and Negates: How these go together is more of a guideline. First ask yourself what turn your deck plans to win. I typically include a base of 4 negates and add 2 negates for every turn past 3 that I plan to win. Then I adjust from there based on the capabilities of my deck and those negates to effectively defend, control, or shut down an opponent's turn. For example, a deck with Shugesh/Explosive Spirit can effectively count that combo as another negate. A Deadly Defender with King Vegeta's Surprise Attack acts the same way. Blue has many defensive options (Senzu, Yajirobe, specially powerful negates like Dimension Magic and Mafuba, two different Defenders, etc.) and doesn't need to run so many negates. This is also where I define what my "primary" color will be. What color energy are you most likely to leave open when you go on defense? Skew the negates that way. In a mixed Blue deck, you might run Whis over D Magic simply because you want to be able to untap the opposite energy for a King Vegeta's Surprise Attack or Crusher Ball.
Energy and Battle Cards: pay attention to how much and what kind of energy your soldiers need (obviously). This plays into your "primary" and "secondary" colors. Typically, I try not to include opposite colors that need 2 or more dedicated energy in a deck. A Blue leader running Deadly Defender Vegeta (costs 3 with 2 dedicated Blue energy) and Kami Power Piccolo (costs 4 with 2 dedicated Green energy) means that to play the most efficiently, you HAVE to have 2 Blue and 2 Green energy on turn 4. That can most likely happen, but bad draws, hand destruction, missplays, or any kind of awkward state can affect how your energy is played. It is typically better to allow one color to require 2 or more dedicated energy while the other plays cheaper supplement cards that support your strategy. That allows you to run 2/2 energy on turn 4, or 3/1 and still be able to play the most efficiently.
Extra Cards: these are always a double-edged sword. They provide powerful effects, but have one less "basic" use than a Battle Card (Battle Cards can be used for energy, combo, and attack. Even extra cards like Senzu or King Vegeta, while adding combo power, cannot be used to swing like a battle card). The trade-off is that usually an Extra Card's effect is supremely powerful over a comparable Battle Card (not always the case, but once again I will use the word "typically"). Only include Extra Cards that are integral to your strategy. Yellow decks and Shenron decks are prone to running too many Extra Cards and can be left dry during an important combo phase. At the same time, it is very hard to build a Frieza deck that doesn't benefit from Cold Bloodlust. Be mindful of your combo phase when including Extra Cards. The last swing of the game almost always comes down to your hand vs theirs. You do not want to be left with a hand full of Planet Vegetas and Cold Bloodlust when you are defending your last life.
Staples By Color: outside of Senzu, there are very few universally good "staples" so this is more of a list of commonly used cards in every color that approach the omnipotent state of "staple" and are cards that you should consider when building in these colors.
Red: Furthering Destruction Champa (and his Supreme Kai counterpart), Unbreakable SS Son Goku, Intensifying Power Trunks, Fearless Pan, Chain Attack Trunks/Zen-Oh The Plain God, Bodyguard Ledgic, Afterimage Technique
Blue: Senzu Bean (fucking duh), Unyielding Spirit Trunks, Awakening Talent Pan, Burnished Bonds Borgos, East Kai Keeping Watch, Objection, Dimension Magic, Whis's Coercion, Courageous Heart Yajirobe, Ultra Instinct Son Goku, Surprise Attack Vegeta, Ki Barrage Trunks, At All Costs Vegeta, Gogeta Hero Revived
Yellow: Crusher Ball, Flying Nimbus, Bardock The Progenitor/Adoptive Father Son Gohan/Scrambling Assault Goten, Planet Vegeta, Time Magic, Unwavering Solidarity Shugesh, Cold Bloodlust (For Frieza, Ginyu, and the new Broly), Bad Ring Laser
Green: Newfound Power Son Gohan, King Vegeta's Surprise Attack, Nail The Namekian Ace, Kami Power Piccolo, Combo Killer Analiza, Full Power Energy, Infernal Villainy Cell, Shocking Death Ball, Android 20 Vile Creator, Hidden Awakening Kale, Son Goku The Awakened Power
Black: Minus Kili Zone, Dark Power Black Masked Saiyan, Time Control Chronoa, Relentless Destruction Mira, Supreme Kai Of Time The Light's Guide, Time's Choice Supreme Kai of Time, Desperate Onslaught Bardock, Mira From The Darkness, Shenron Flight Of Majesty, Trunks Power Overseeing Time, Dimensional Banisher Fu, Masked Saiyan The Mysterious Warrior, Mira Creator Absorbed, Scientist Fu, Beyond Darkness Demigra, Fu Shrouded In Mystery.
Sometimes it is better to start with what Battle Card strategies before picking your Leader. Sometimes it's better to start with the Leader.
Try not to include both Overrealm and Sparking in the same deck.
Keep counters in mind. If you struggle against Frieza, sideboard Minus Kili Zone to handle Cold Bloodlust.
Pay attention to which turns are lacking plays and which turns are crowded. A deck of powerful 4 cost cards will not be able to play all of them in the same game, rendering them useless.
Typically, 0 +5K combo power is more useful than 1 +10K, unless it includes powerful effects.
Hand advantage is key. In this game, every card serves at least 3 purposes (energy, attack, combo, effect; Any or all of these). The combo step is very important. In the last few life, the victory usually goes to the player who simply has more cards in hand.
Don't tap out unless it's the first turn or you are swinging for game.
Ok so some of you may have different opinions. I welcome and respect any opinions or edits that you might make. Thanks for reading!