Splatoon 2 - How to Use the Explosher and Custom Explosher

I'm not good at Splatoon, and this weapon isn't doing me any favors. Music Used: Night of Fire - Niko Neo Exdeath (FFV) - The Black Mages Fire Emblem 3 Houses Main Theme Kurayaminoku (FFIII) - The Black Mages Corneria - Super Smash Bros Melee OST [ＣｈｒｏｎｏＷａｖｅ] ¦ [クロノ波 ] (A Lo-Fi Hip-Hop/Vaporwave Remix Of Chrono Trigger) - Grand Cross (FFIX) - The Black Mages Breath of the Wild Medley Final Battle - Zelda 30th Anniversary Concert You