Dude, regebro, although your tips are useful, you didn't answer the question!
If the tape path was "obvious" to a new analog user, then he wouldn't have asked.
Okay.
- Place the full reel of tape on the left [supply] hub, & fasten.
- Tape should be unwinding off LEFT edge of LEFT reel, as reel spins CCW.
- Thread tape; FROM LEFT TO RIGHT
- UNDER LEFT TENSION ROLLER
- OVER RIGHT IDLER ROLLER
- UNDER THE ENTIRE TAPE HEAD STACK, incl UNDER TAPE LIFTER
- BETWEEN CAPSTAN & PINCH ROLLER
- OVER RIGHT IDLER, [serves as counter/tach roller]
- UNDER RIGHT TENSION ROLLER
- UP to RIGHT SIDE of RIGHT [takeup] REEL
- WIND tape onto takeup reel, CCW, while holding tape on reel with finger.
When that all seems secure, press PLAY & wind about 30 seconds of blank tape onto the takeup reel as leader. STOP & press RESET, to zero the tape counter. 30 seconds of leader tape is PLENTY, since the 388 can stop on a dime! You may want to record onto the leader a 0VU A/440Hz reference tone off a keyboard, or a 1KHz tone from a signal generator, if available.
The recommended tape is Ampex/Quantegy 457, which is an 1800' equivalent of 456, which only comes in 1200' reels. Both 456/457 tapes are suitable and recommended for the 388, but you'll need the 457/1800' length if you want to use the 388's LOAD function.
The manual is a recommended purchase.
WTG on getting the 388. It's so feature packed, that it was never equalled in the industry! Ever!