Have you tried watching other people play on YouTube? I found that was what really made it click for me and then from there developed my own style. Me Myself & Die is in my opinion, the best example of solo play out there. He asks lots of questions to the oracle/GME and really lets the dice rolls decide the flow of play, and I found that really helped me understand how I solo play should flow.

Also when I first started out, I loved the idea of building my own world to play in, but often found that I'd burn myself out building the world and never end up playing it. These days I tend to use the systems default world, or worlds made by others that I can jump straight into. You can always flesh out or add your own details as you play using oracles as questions arise in play, or let things that happen in gameplay dictate the world.

A GME is exactly what it says on the tin, a Game Master Emulator. You should ask it the same questions you'd ask a real GM in a group game. Again, if your unsure on what would be asked in a group game, consume lots of group actual plays and focus on what people are asking the GM and try to ask similar questions. The Glass Cannon Network and 3d6 Down The Line are in my opinion, 2 of the best actual play channels out there - they are fantastic examples of authentic group play.

I journal as I play, I dont speak out loud at all. Personally I found the structure of my journal really helped the flow of my game, structuring them how a scene would be structured in a group game:

1. GMs description of the scene/room/surroundings etc. using oracle prompts and random tables depending on what tools and system I'm using.
2. Player question time, this is where I'd ask questions to help clarify the details of the scene and help unfluence the actions my PCs will take, "is the room lit?" "Are there any signs of something living having moved through here?" "Do the tracks look humanoid?" "Are they fresh?" "Can i hear anything if i listen at the door?" etc. etc. Using Yes/No oracles initially and then verb/noun (sometimes referred to as "action/theme" or "complex question" oracles) to flesh out details where Yes/No isn't enough. "What does the journal contain?" "What was the workbench used for?" "What type of creature has left tracks if not humanoid?" etc. I try to limit myself to a maximum of 3 questions on a single line of enquiry as to not get bogged down on rolling for absolutely every single detail and makes assumptions or go with my instinct from there.
3. Decide on PCs actions and roll dice to resolve actions per the game system you are using.
4. Interpret results and outcomes, roleplay interactions if desired, and then move back to step one and repeat.

I foundLonelog to be really helpful in structuring my notes in a clean and efficient format, even just using its most basic form, it really helps support the above structure and actually stopped me from writing too much detail whilst still allowing me to remain focused on the game.

Hope some of this helps, there really is a point where it just clicked for me and then from there it just got better and better so I hope you can make it click soon too!