I'm not very good at writing out combo guides, especially for decks like this that don't have one big long combo, instead using a bunch of smaller combos that string together, so bear with me.
The combo starts with getting a Junk Synchron in your hand and a non-tuner level 2 in the grave. You can achieve this easiest by using Quickdraw or Junk Converter to send the card, and opening Tuning, Junk Converter, or just Junk Synchron itself. From there, summon a level 2, Synchron Carrier lets you summon Junk Synch, Caligo summons itself when Junk Synch is on the field, and Doppelwarrior summons itself when Junk Synchron revives a monster. Next, go into Junk Speeder, summoning another Junk Synchron and a Jet Synchron. From there, summon Hyper Librarian, then turn Jet Synchron and Junk Speeder into Stardust Charge Warrior, drawing one from Hyper Librarian and one from Charge Warrior.
The combo is pretty fluid from then on, with it really not having any one defined set of cards.
Good ending cards are Draco Berserker of the Tenyi, Psy-Framelord Omega, Crystal Wing Synchro Dragon, and Shooting Quasar Dragon (which can be made with Martial Metal Marcher, Herald of the Arc Light, and a Junk Speeder/Hyper Librarian
Example first turn board: https://imgur.com/a/0Bde1uw
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