One of my new favorite techniques in song writing doesn't involve effects, sounds, or DAW in any way...
 
Making a song with major chords sound dark.  Trent Reznor is a wiz at doing this.  I always liked his sound, (not necessarily his lyrical content), but just recently realized that almost all of his song are not only based on a simple pattern that he loops and layers, but they are almost all in a major key.  Yet they sound so dark.  I really love that technique and have tried it on a few of my own songs (with more positive lyrics lol).  
 
Another technique that I've recently gotten into is experimenting with multiple time signatures.  
 
What are some of your favorite song writing techniques? 

Morrissey of The Smiths was great at making songs in a major key sound melancholic. It was partly because of his voice and partly because his melodies tended to jump back and forth between the major 3rd and the 5th of the scale a lot - which is in itself a minor interval. 
 
I use multiple time signatures a lot. My projects are often a real mess because of it. Aside from electronic music I've always had a deep interest in folk music, particularly British singers like Bert Jansch, and because of that my ears are very attuned to the idea of letting lyrical content dictate bar lengths. Folk singers will often shorten or lengthen bars to fit the lyrics they're singing, so you might get a song in 4/4 which has the occasional bars of 3/4 or 5/4 in order to accommodate a lyric which wouldn't otherwise fit. Although most of my music is instrumental, I have picked up a lot of that rhythmic style over the years. 

nothing beats a piano, scratch pad for lyrics and maybe quick recording to USB (or even cell phone) in case ideas start flowing faster than you can jot them down ... sometimes I throw in a simple (hardware) loop player but nothing fancy so that it does not distract.
 
A DAW (well, ANY DAW) just has too many things to setup to record. Even if you have all in place and organized in templates, it sort of breaks the creative flow when working on tunes & chord progressions & lyrical content.
 
It's a different story when the main parts are written (one verse, chorus, maybe a bridge or interlude). then the DAW can work its magic, but that I no longer call that song writing; that's already arranging to me.

My techniques has yet to be codified as it continually fails.

My best technique is taking a shower or a walk.
Or looking up the word codified.

For platform and location independence I use Simplenote - a quick text-only note pad which comes as an Android app and also browser-based for PC/laptop. It updates across the platforms reliably. I also use HiQ mp3 recorder app on the phone for quick access to recording ideas off guitar (or banjo) or keyboard (I don't do lyrics). I also use the Box app (and web-browser based) (in fact I also use BT cloud Google cloud and Dropbox, but tend to gravitate to Box for no real reason).
 
For text notes of tunes I tend to use my own coded way of numbers, e.g.
 
[key Cmaj,swing]  .5 / 61 16 1. 21 / 4. 32 32 3. / 21...  
- this of course is an approximation of Help Me Rhonda. I would like to point out that I didn't actually compose that particular melody. 
 
jdf

My favorite is whatever happens to work at the moment of inspiration.

I like to make weird chord progressions work through melody.  Radiohead does that really well.  Although when I try, it seems to turn out not nearly as weird as I intended. 
 
I wish I had a technique.  Really..sometimes it's sitting around playing the acoustic and whisper singing...sometimes I'm on the drum set and a riff comes to me...sometimes it's a pure DAW experience where I track ideas and then play along with other instruments as if it was a band jam...
 
most stuff comes from inside my head, with no instrument around, driving around or at work...then I fear forgetting it, so my phone has about 20 short audio files of me mouthing guitar music with senseless lyrics in between breaths...hope no one hears that, would be embarassing..

I'm still casting about for a technique. Haven't found one yet. But I've only been at it for 50 years, so I'm optimistic.

I like what Herb and Bit said for sure ....
 
One thing I like to do as far as inspiration goes is to sit down and just play my guitar wile listening to the overtones and possible melodic voices that are already contained within the chords voices itself ...
 
Using a C major chord for example , C E G ...most peoples ears are trained enough to hear the C as the root , the E as the Major third and the G as the fifth ...
 
IMHO , here's where it can get interesting with a little musical game  I like to play ...
For starters I may take the C E or the G  building blocks of a C major triad and build a  chord making those notes the major or the minor third of a chord , the fifth of a chord  Major , minor 7 th ect ...or the root of a chord ...major , minor , 7 th ect ect ...
That alone can open up a lot of new doors even if my chosen target tonality was to stay true to the sound of C major ...
The C as a root we all know how it sounds, The C as a minor third in relationship to an A note can imply  a minor third sound the sound of A minor the 6 th degree of the diatonic tonality of C Major
The C as a major third can imply an A b major chord , the C as a b 7th in relationship to D can make and become a D7 chord ..
The C as a major 7 th tone in relationship to D b  can become and imply a Db major 7 th chord ....
 
For the sake of what I'm suggesting if you were able to grab your instrument and play a C triad C E G and then play any number of the possible variations I have just mentioned as chords , you would hear very easily a number of very popular chord progressions you have heard a 1000 times before ..
 
Why not try it , play a C chord first , then build a chord I have mentioned using the above concept , then play  the C chord again ...Your ears will know I'm speaking the Truth ...
 
for the sake of brevity I will leave it at that for now ...
When  one is so inclined , and if they took the time to do the same with the E, and G notes as I mentioned as what I did with the C note , they would soon discover that they would have and hold the key to unlocking thousands of new possibility's well within their musical grasp 
It can do a lot deeper than that of course ...as deep as you want to go ....
IMHO , this is a good place to start ,
 
all the best,
 
Kenny