How Do I Build A Strong And Competitive Yu-Gi-Oh Deck?

well my good man, you might wanna try & make as many combinations as you can, cause thats what wins duels, not strong cards. like the blue eyes for example, is very difficult to summon it normally. so what you wanna try & get is some sort of effect monster or spell or trap card that can special summon it without too much of a hle. same for if you get the blue eyes ultimate from me. & i have a combination to get it out easily as well. the blue eyes shining might be your strongest card since you have so many dragons, & it can only be destroyed as a result of battle so your good there. you wanna try & incorporate it as much as you can. dont lose it. & splitting up your dragons & dinosaurs might be a good idea as well. it'll come back to bite you in later duels. hope i helped! =D