I started out with translation, but really only because I started out reading with a novel series that I knew I wanted to translate once I’d raised my level since the current fan translation is straight-up just MTL’d (a.k.a. it’s terrible), and I also didn’t translate everything as I went. I’d type everything into a document to go back and translate at leisure, while also translating some as I went, whether because it was something I knew how to translate with few to no lookups (which, of course, didn’t start happening all that often until I’d gotten further) or because I wanted to figure out what exactly that line/paragraph/section was saying or because I liked the line and wanted to figure out right then how to put it in English nicely.
It helped a lot of course with typing in Japanese and using an IME (at least my laptop’s IME), but I feel like it also helped me with learning readings, since 1) I couldn’t just leave a blank in my head where there’s a kanji/word I don’t know how to read or else just go, “Ehhh, I think it was something like such-and-such, close enough,” I’d have to look it up (Well. For the most part. There’s always the occasional one where I’m like “Well I don’t know how to read this word since one or both kanji clearly are using a reading I don’t know, but I can produce them both separately, so I’mma just do that”), and 2) I’d have an impression from typing it before to guide me to the right reading. Also helped me recognize e.g. 担う vs 担ぐ and 拭う vs 拭く conjugated, since if I got it wrong, I’d know immediately. I’m the type of person where doing something physically helps a lot to get it to stick in my brain better, which is why I like fill-in-the-blank and absolutely cannot do regular old flashcards.
Of course, it doesn’t necessarily help with meaning, but it’s a lot easier to look up words when you know the reading.
I’ve never translated line-by-line, and I also have a tendency to just skip over lines where there’s more than one or two unknowns since I have difficulty juggling that much info in my head at once. I may or may not look up all the unknown words in the sentence (depends on my mood, how much energy I have, how important this line feels for overall understanding), but I usually don’t try too long to piece it all together before moving on unless I’m really not getting something and it’s because of that line.
And outside of that one series, I rarely translate except a few lines mentally here and there where I can’t get the meaning unless I do, and even then it’s often just a part of it, like where there’s a grammar point I accidentally overlooked, or a particularly long relative clause where I lose track of what particle refers to what, etc.
Mostly I try to just read, and how much I look up varies depending on how much energy I have for it that day. Even early on, I’d surprise myself with how much I could understand even when I didn’t look up much if anything. I don’t like intensive reading, I find it a bore and a giant slog, so the closest I get is extensive with some intensive leanings. It might take me longer, sure, but I get to read more and enjoy myself more this way, even if I understand less. And I will reread, but not immediately. I don’t have any novels that I’ve reread yet, but I do have a handful of manga, all read at least a few months after the first time.