Mmm 
Loki manifests in anyway he can. He sends omens (mostly spiders which I hate 
) and it will be an unusually large amount, like a nest (I walked into the first one in the bathroom, they were all over the mirror, the second one was across the ceiling in my son’s room, and the third was like a door beaded curtain across the conservatory), I assumed at first it’s cuz I live in the country, but a fellow witch here said, no, that’s not normal as she lives in the country and doesn’t get nests, upon checking neither do any of my neighbours 
. He changes channel on my radio. This first happened years ago, when my geto blaster kept switching the radio on after midnight, it wasn’t plugged in, no batteries! My hubby got so annoyed with it, he drove half way down the street in the middle of the night and threw it into a community bin. 
This was before I had embraced Loki so we were a little freaked out by it.
I’m not great at meditation, I do it but my mind wanders, but @starborn has this post with a good ritual for communicating with deity/demons
A Spiritual Phone Call: Ritual for Speaking to Spirits
Check it out, see if you like it.
Loki talks through my cards, alot through runes, I’ve had the odd dream and I only pay attention to dreams if they reaccur, like over and over, then I know it’s something extraordinary.
I do get images flash in my mind of the different energies of Loki, and they appear in human form apart from the hooded figure. The first time I saw that Loki was during a reiki session with my reiki healer, I asked her about it and she said it’s probably a spirit guide or someone reaching out.
Loki is quite unusual in that he’s very hands on and gets right in your face. My hubby saw him twice as a ghostly face over my face looking back at him whilst we were at McDonald’s, this was before he embraced Loki, it freaked him out a bit.
Not all gods/demons work this way, but if you read up on books by fellow Lokeans they all seem to have supernatural experiences so I think it’s just the way he works.
He’s the god of chaos, so pretty soon, if he’s interested you’ll notice a shift in your energy and the energy in things around you. At first it can be quite stressful, the chaos energy, it can make you feel, well everyone else’s life is smooth running, why do I get all this s**t!. But gradually he teaches you how to flow with it, and then it’s actually very freeing (most of the time ).
Hope this helps. I wouldn’t see signs in everything, I think for me it has to slap me in the face, but maybe that’s just me 
Ps, thinking on it more, definitely read up on deities/spirits that resonate with you, as they do tap into your energy, you’ll get a feel for one that’s unique to you, then you can look back and see how long they’ve been a part of your life.