I have been doing this for a long, long time. I started playing Christmas Day 1979, and developed my own adventures by early 1980. A lot of the articles I found inspirational come from early Dragon magazine, and those are going to be hard to find. But, feat not! 'cause the basics are not all that difficult.
(1) Brainstorm. Take some paper, and write all the cool ideas down. Find links between them. Let the main ideas begin to percolate through your subconscious.
(2) Never base your adventure on expectations of what the players will do. Players always do something else. Make sure that they have meaningful choices. Make complex maps, with multiple routes, unless there is some important reason not to.
(3) The goal of players in an adventure is to control the situation. The more they control the situation, the less risk for their characters. Also, though, this is boring, so the adventure writer must throw in enough situations where things can get out of control so the adventure is exciting. That way, the GM never has to cheat. If the animated wooden statues are defeated easily by wood wyrding, some fool will drink the enchanted wine, or get caught in the burning web of a daemonic spider.
(4) Likewise, it is a truism that, unless the GM cheats, no group of players will ever find everything. Therefore, feel free to put all kinds of odd treasures in interesting places. Seed enough potential "Woah! That's cool!" moments so that the players have a chance of stumbling into at least one or two of them.
(5) Be true to the setting, even if it means the PCs get hosed/get a huge reward. Place what you think makes sense in the location, even if it seems out of keeping with a "level X module". Allowing the setting to make logical sense, even if the players never discover the logic, is important for two reasons. One, no matter how detailed your adventure, the GM is going to be forced to make a judgement call sooner or later, and the overarching logic is going to be of help here. Two, the overarching logic is felt by the players in the presentation, even if they do not understand it. They need to be able to trust that it is there.
(6) Context, context, context! Once you know what is going on in the setting, and what creatures you are using, consider the clues and evidence that they leave behind. The more the players have to guess with, the more engaged they will be. If these clues make an encounter or two easier, that's okay. That's great, actually. That's the reward for paying attention.
(7) If you can, put in an area or two where new PCs can be logically introduced. The larger the adventure, the more important this is. Harley Stroh's 0-level DCC funnel adventure, Sailors on the Starless Sea, offers an excellent example of this principle. Likewise Jon Marr's funnel adventures, Perils of the Sunken City and The Ooze Pits of Jonas Gralk.
(8) Try to remember that two things are happening - the PCs are exploring the adventure area, and the players are around the table playing the game. If you can bridge the two in some way that makes logical sense, you should consider doing so. For a really good example of this, see Tales of the Scarecrow from James Raggi. Likewise, some effects in Death Frost Doom depend upon player seating around the table. Finally, my own Bone Hoard of the Dancing Horror has a nasty knock-on effect when a PC is felled by the titular horror and the player then engages in table talk.
(9) Develop the material enough that any prospective GM can understand what you are trying to convey. When writing fiction as a younger man, I produced many an unsaleable story simply because I failed to realize that I could not assume that the reader would "get" what I was trying to say unless I actually said it. I could not simply assume that the reader knew some specific thing that I knew, and I could not assume that the reader would care enough to find out about it because my story felt unresolved. That is not a fault in the reader; it was a fault in me as the writer. When I learned this lesson, I started selling stories. Adventure writing is not that different in this regard: Be clear about what you are writing. Say what you are trying to say, and say it clearly.
(10) Finally, have fun! Let your own unique voice and sense of humour come through. If that means you disregard any or all of the above, so be it. You should create adventures that you find satisfying. If you don't feel satisfied, what are the odds anyone else will be? And, if they are, what difference does it make? Better faint praise for something you are proud of than overwhelming acclaim for something you find embarrassing!
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