How do you put an Effects pedal inside an electric guitar?
Its not common practice to put effects into a guitar. The term effects loop is usually used with an amplifier which has an output and input socket which are (electrically) located between the pre- and power amplifiers. Look for a pair of sockets marked FX OUT FX IN or similar. There’s a number of schools of thought on the placement of effects, but the most commonly subscribed to is to have distortions before modulations and delays. there’s nothing wrong with changing this order to suit your sound though. Often pedals are all positioned sequentially between the guitar and the amplifier, and rack mount effects located in the amplifier’s effects loop, but there is nothing to stop you putting a delay, chorus, flanger, phaser or such like pedal in the amplifier’s effects loop. I would not recommend using your distortion effects here though.