I think the "networking" spamming on there is fairly accepted. But you will be drowned out by literally every other guy doing that also.
What I noticed that's working is from when you start a fresh account, start by adding only people very SPECIFIC to your niche.
Exclusively add those people, then add their connections, then add the suggested connections, and continue that for a month.
You will then start seeing connection requests coming your way from industry-related people.
In the meanwhile, start working on a sales funnel for privately messaging people.
Introduce yourself, "Thanks for connecting" etc, etc, etc
Ask what they do.
And after that, tell them what you do.
I think that's pretty much it. It's a more interpersonal approach as opposed to copy-pasting a HUGE essay and sending it out to all your connections. I get at least 8-10 everyday and I definitely ignore them because I can already tell from the first few sentences that they're full of BS and just wanna sell their social media marketing services.
I have a colleague who ran LinkedIn ads for his label. According to his experience it wasn't worth it. It seems to be only beneficial for corporate-level activities. But hey, why not give it a try at a low budget.
Regardless, have fun with it. LinkedIn is an absolute BORE, so if you have a slight bit of personality, you might stick out.