Can’t find a build? Just spend some time going through the wiki reading what each trait does, noting the ones with synergy, and especially making note of the ones that sound fun to you. Your desired weapon(s) and the heal/utility/elite skills should be factored in as well. Then distill that list down to the ones you can actually equip.
Then look through all the runes and sigils to find ones that fit and/or sound fun to you. Some may be locked behind content, but there are plenty to choose from.
Now, maybe it becomes a wish list because the armor is expensive or time-gated, or you have to collect 100 Pristine Spores first (whatever), but there, you have a build.
Now, if you have specific purposes in mind — group content — then paying attention to what people will accept is a consideration. But you could have a “dungeon set” and a “what I enjoy when running around PvE set.”
Googling things like “gw2 warrior greatsword build” may give you some ideas of things that work together to get you started. But don’t feel like you can only do what other people are doing.
