How to Use a Guitar Pedal
Okay, so you have an average pedal in front of you. No matter the manufacturer or the effect in question, they have some basic features that are the same for almost any variant out there. First, you have the footswitch that turns the effect on and off. When it's turned off, or in the so-called "bypass" mode, your signal is unaffected. All the pedals out there have an LED indicator, usually a red one, informing the user whether the effect is turned on or off.
However, all the pedals require electrical power to operate, and if there's no power source, you won't get the sound going through it even if the effect is turned off. The vast majority of pedals are powered by the standard 9-volt battery or with a 9-volt AC adapter. In most cases, manufacturers will recommend their own adapters which are usually a bit more expensive, but you can use any standard adapters as long as they have the same voltage and are of decent quality. In some cases, pedals require more power and are powered only through a specialized adapter.
Replacing the battery might seem like a chore, but it's something you'll get used to. In most cases, the pedal's footswitch, which is the moving part, can be lifted and underneath you'll find the battery compartment. This, however, depends on the pedal that you're using and some of them have other ways of holding the battery. Either way, you should always read the manual before trying to do anything on your own.
Up next, we have input and output. Standard pedals usually have an input on the right side and an output on the left, where you connect it to a guitar amp. All the pedals are connected using standard 1/4 inch guitar cables.
Now we get to the most exciting part and dialing in your tone using the controls on the pedal. Guitar pedals usually have knobs that operate like the ones you can find on an average electric guitar. These knobs control certain parameters, depending on the type of effect that you're using. If we look at an average distortion or an overdrive pedal, these usually have volume, drive, and tone knobs. In some cases you'll have dist pedals with 2-band or 3-band equalizers, allowing you to have more control over your tone.
Most pedals will usually have the master volume control, no matter the type of effect. Different modulation effects, as well as delays and reverbs, will have a knob labeled as "blend", "mix", or "dry/wet". This one determines how much of the processed signal will you blend in with the unaffected signal.
Some other, more complex effects out there, like some filters, will have an abundance of different controls, but these are usually not recommended for beginners as they require some experience to implement properly.
Wah, volume, and expression pedals
If you're into guitar-oriented music, you're most definitely familiar with the wah-wah effect. These pedals have a "rocking" part that allows you to alter the tone and, in some way, bring it closer to a human voice. Wah pedals also have an additional knob for controlling the depth of the effect.
While they look similar to wahs, volume pedals do nothing exciting but are of extreme importance if you're playing in a band where the dynamics are a priority. These also have a rocking part that controls the output volume of your signal. There is also an additional knob for controlling the minimum volume.
Expression pedals do nothing on their own but are used in pair with other units that support the expression pedal connectivity. These look exactly the same like volume pedals but only control certain parameters depending on the pedal you're pairing it with.
Of course, there are also some more advanced features, depending on the type of effect pedal that you're using. Some distortion pedals have additional footswitches for more distortion or have some other controls that affect the shape of the overall EQ.
As already mentioned, some modulation, filter, or other effects have the option to be connected to an external expression pedal.
Another thing to consider is whether the pedals have true or buffered bypass. This is something that beginners will most likely not care about, but will definitely be of more importance in their advanced stages of playing. The opinions on this vary and some prefer using true bypass while others are more fond of the buffered pedals.