Ignition switch help

So I went to replace the ignition switch on my mtd and I think I mixed some of the wires up when I went to put the new one on could someone tell me how to Check which wires go to which port? And could you explain it in simple terms since I'm inexperienced with small engines thank you

Hopefully you got the right one. I am also guessing that it wasn't a plug on back side but individual wires with connectors.

Back side of the switch should have some letters.
G - Ground
S - Solenoid  (Small terminal to fire it)
M - Magneto, kill wire from magneto/coil goes here.
B - Battery, should connect to battery or the battery side of the Solenoid (Big terminal, not the starter side)

You may have other letters like L-Lights, A1 or A2 that connect to different things like fuel solenoids, alternator and safeties. Little more information like model of MTD, has the wiring been modified. Pictures?  Hope some of this helps?

Here's a schematic from an MTD I had : https://www.partstree.com/parts/mtd/mowers-lawn-garden-tractor/14as825h118-yard-machines-garden-tractor-1997-sam-s-club/electrical-system/

Yours should be similar.