I can't figure out when to use these words. It seems to me that both of them mean that the action has completed. And yet one of them means a "positive" result.
Since you didn't bring in specific questions, below are my random thoughts.
In general, "好" is an adjective that means "good", or "okay", such as "好學生 - good student", "很好 - very good", or simply "好 - okay/good". Note, "好" is a noun after a possessive pronoun, "別忘了他的好 - don't forget his goodness".
When used as a verb, the pronunciation of "好" changes from the third tone (hǎo,ㄏㄠˇ) to the fourth (hào,ㄏㄠˋ), as in "他很好動 - he likes to move around a lot", "她很好哭 - she likes to cry a lot = she cries a lot", and "他很好事 - he likes to stir up troubles, or he likes to mind others business".
"好了", as suggested by "了" in the end, means completion of the act specified by the leading verb, or a change of state. For instance:
車子修(v)好了 - the car is fixed.
作業做(v)好了 - the homework is done/completed.
"好了" as, or in a phrase:
好了. - Enough.
太好了 - great or good beyond expectation.
不好了 - bad news or something (bad) has happened.
好 before a verb can indicate the verb itself is satisfying. The simple 好吃 as an example: (the food is) satisfying to eat.
好 after a verb can show that the verb is completed satisfactorily. This version is usually combined with 了 which also shows completion (note that 好了 with no verb can mean something is ready etc.) An example: 他做好了 He does his work well.
Also note that this can also be used in the negative, but you don't ever use 了 for negative completion. Example: 他做不好。 His work is unsatisfactory.
好 has many meanings and not all of the times it is around a verb or 了 will fit these two uses, but this should help clarify what you're talking about.
I am not trying to confuse you, but life is just not always black or white. There is no 1 rule governing all possible uses of 好、好了。Don't waste your time searching for it!
You can modify the following sentences according to the () and the sentences are still acceptable.
他已穿戴好了，包括鞋子。(can remove 了）
He was fully dressed, including shoes.
你要是不懂，尽管问好了。(can remove 好了）
If there is something you don't understand, don't hesitate to ask.
她倚在门上，上好了门闩。(can remove 了）
She leaned against the door and slid the door bolt closed.
他已事先写好了答案。(can remove 了）
He prepared his answers beforehand.
for the meaning of "done", better to mentally structure like (((V)好)了), so that the problem is mostly about usage of 了.
you could say 做好了，做好之后xxx，做好没？，做好也不够，做好是xxx的前提，先做好再说，把这件事做好. in these cases, you may append 了 for most of them, but in some certain cases it might be considered extraneous. without 了, it'll mostly sound like "to finish something, to do something well" where the phrase could be used as a noun.
here 好 is in the same place as 起 in 拿起、提起、唱起 and 下 in 放下、坐下, also 完 which is similar to 好. 趋向补语：来、去、进、出、上、下、回、过、起、开……
barely saying 好了（好了吗？没好！）is a special usage, or say here 好 is being used as a verb itself, although it also means generally done.
（尽管、干脆、还是）V好了 is a totally different usage, not related to "done" at all. mentally structured like ((尽管(V))好了), 好了 is grouped special word.