If you arrange many pedals on a complex pedalboard the question of the order of the pedals arises. This matter is more complex than one first might think. Therefore one has to note some rules and some exceptions.
In first place one mostly places the tuner. The advantage of this placing is that you can tune your guitar precisely without turning off your modulation-effects. Another possibility is, to connect the tuner to a special output of a volume-pedal or a looper. Thereby the tuner is totally removed from the signal-chain and can stay turned on all the time. Furthermore it does not influence the sound by its built-in buffer.
Envelope / dynamic effects
Dynamic effects like the Wahwah or the Autowah should also be placed in the first places of the effect-chain. Notably the Autowah (the envelope, which is controlled by the attack of a string) is able to react more precisely to the direct signal.
The Wahwah can be found in front of, or behind a fuzz-pedal, but always in one of the first places of the effect-chain.
The overdrive is also mostly placed at the beginning of the chain of effects. At this position it reacts most dynamic. It makes sense to place overdrives that reproduce the sound of an amplifier further back in the arrangement.
Booster or low-gain-overdrives can be placed behind a delay. In this way you can imitate the sound of an old tape- or analog-delay.
The compressor is mostly used in front of the overdrives, which gives you a nice and compressed overdrive-sound. But on the other hand one cannot control the amount of gain of the following drive-pedal by the attack of the strings. Because of this, I personally would always place the compressor behind the overdrive. If you put it into a moderate tuning the sound will be more compact and a little bit more like an overdriven amp.
If you use the volume-pedal at the beginning of the effect-chain it functions just like the volume-pot of a guitar. By this one is able reduce the volume and control the amount of gain of the following overdrive- or distortion- pedal.
By using the volume-pedal behind the overdrives, the amount of gain will stay constantly even if you reduce the volume. Delays and decays will not be cut off if the volume-pedal is placed in the back of the row.
Pedals like flanger, chorus, phaser, uni-vibe and tremolo are also known as modulation-effects. In this article I tell you more about the differences between the several modulation-effects.
There are many ways to arrange modulation-pedals. Mostly they are placed between the overdrive and delay/reverb. One can place them as well in front as behind the overdrive. In my opinion the uni-vibe sounds much better in front of the overdrive-pedal.
The tremolo can also be arranged in different places. Many times it is placed in the last space in front of the delay and reverb. But also behind a delay or maybe even behind a reverb-pedal it is able to create pretty nice rhythmic modulations. You can find reverb and tremolo integrated into old Fender blackface or Fender silverface amps. It is also placed behind the reverb and therefore creates three-dimensional vibrations.
Delay and Reverb
Delays and reverbs are mostly placed in the back of the effect-order. If they have got stereo outputs it is interesting to try them with two amps. There is nothing against using the reverb in front of the delay. Especially if you want to create ambient-sounds they can sound in a certain way “vanishing”.
You see, there are many ways to put your pedals in a certain order and I think that there is no “one and only” rule. It is worth it to try different orders depending to the sound you are willing to create. A Jimi Hendrix cover will require a different order of pedals than a shoegazing-song.
You can find an overview of the story of effect-pedals here.