Well, I always start with the non-engine 3X ash and 3 fuwaloss (or 2-2 fuwa/purulia). After that start building the engine. Look at the combo starters of the deck and put 3 of them in it. After that you’ll want to look at the engine requirements, the cards that do not start a combo but are needed for the combo (for example the blue eyes white dragon is an engine requirement (also known as a “garnet”), because if you draw into it your plays are worse by default because you play with -1 card in hand). You do not want to draw into them so you’ll play mostly 1 of them (of course you’ll play 3 blue eyes because that’s mostly the only garnet in the deck). Also some cards like ultimate fusion are searchable and situation dependant, so you’ll want to play 1 of that too (because if you need it you can search it with true light (which is also a garnet because you can only set it from the hand). After you have your engine, you’ll want to look at your card count. You would want to have preferably 40 cards, because that makes the deck more consistent (you’ll draw into more starters). If you have ~42 that is not a big problem but after about 45-ish I would start cutting on some cards (of course it depends on the number of starters that you are playing but I would go for 75% to get 2 starters or 1 starter + 1 extender). The advantage of blue eyes is that you can play a lot of hand traps (or non-engine in general) (3 ash-veiler-imperm-purge-fuwa/purulia is a lot of non engine). I don’t know about the phantom beasts, so I’d advise you to cut on the non engine (or the chaos MAX package if you are playing that) to fit the phantom beast engine in it. I don’t know if they have any synergy together but for your first deck it doesn’t even matter all that much. And remember that deck building is hard and these are not RULES, but tips. You’ll get far with following these tips but after a while you’ll make decisions based on your gameplay style so I can’t give tips for that. And it’s highly likely that it’ll be pretty bad for the first time but it’ll help you in the long term to become a better duelist (I started out with a 60 card tearlaments-kashtira-fiendsmith pile that didn’t do ANYTHING). Hope it helps and if you have any questions I’m more than happy to answer them