Thanks for the advice, all. Your continued replies are welcomed too.
On a related topic, by the way, how do you go about wandering in various restaurant/bar districts and finding interesting and affordable izakaya to visit and eat in, for example?
When I traveled to Japan last time alone, I found it kind of intimidating/unfamiliar to wander in a random place and figure out what they serve, what kind of atmosphere it would be, how expensive, etc. when you can't read or speak Japanese. Aside from just looking for red lanterns... As a result, I would go to chain places or where things were clearly marked, which led to my eating adventures being not so adventurous.
Walking into random izakaya is my favourite part of japan but it did take me quite a few visits before I really did it regularly. I wish I had've started earlier.
My suggestions
Learn katakana, it's not too difficult, can be learned in a few days and will help a lot as its a case of sound the words out and you know what they mean. Things like salad, fried and dessert are often written in katakana so at least it gives you some concept of what you're looking at.
Learn some basic food related kanji. Beef, pork, vegetables etc. again, gives you some concept of what you might be looking at. Oh, and numbers, make sure you can read prices properly!
Understand your surroundings. Are lots of people eating nabe? Is there a yakitori grill? Having some idea of what they're serving helps you interpret what will be on the menu
Order draught/nama beer once you sit down. It's easy, it gives them something to do so they don't stand around looking uncomfortable and its normal behaviour. It also gives you a chance to sit back, take in the scene and figure out what's going on with the knowledge that your first order was delivered with confidence and understood
Have some go to dishes. For example If they have yakitori you should be able to rattle off 5-10 different types which you'd expect them to have without looking at a menu. Again, this gives you space to think and confidence.
Don't be afraid to ask for recommendations but they work best if you give them something to work with, eg today's sashimi recommendation, or fried food or vegetables. We often ask the table next to us for a sake or shochu recommendation.
I've never made anyone upset in ny izakaya I've walked into and many of my best experiences in Japan started with walking through a door when I had no idea what was on the other side. Don't sell your trip short, just do it.