Now, this is a bit of an interesting topic, as it is highly subjective at best. I suppose I should cover some of the really, really basic stuff before I begin.
Firstly, not everyone has a "PATRON GOD" (or Goddess) in the sense that this deity has been with your forever and will never ever leave you and is the primary influence in your life. In fact, some people don't have any Gods which even passingly influence their lives. While working with deities is quite common, being God-touched -having one or more patron deities with a vested interest in you- is actually pretty unusual. I am gifted with such a status, as is my sister and one or two of my friends, but the vast majority of the people I know are not.
It's not actually a happy sunflowers-and-rainbows-and-puppies deal, despite what some people think. Those who are God-touched have difficult lives, overall, and a number of struggles to overcome. They tend to be tied to Gods because they genuinely need their patrons, or because they are needed for something to be accomplished. Being God-touched is not having everything suddenly made easier for you because you have Zeus in your corner; if anything, everything gets that much harder.
Those involved with energetics can identify those who are God-touched, if they are skilled enough, as a random side-note.
Secondly, most of the time you don't get a say in who or what your patron deity is. They choose you, for the most part, and enter your life when they feel you are ready for them or simply when you need them. Some paths encourage individuals to seek out and choose their own patrons, but that gets a bit complicated when the subjectivity of it is brought into play. I was raised to believe in the Norse pantheon, for example, but my primary patron is Hermes, a Greek God. I had a hard time reconciling that for a while, I admit, and even went so far as to foolishly declare, "Okay, fine, but I need a Norse God to make this culturally acceptable! I'll take Loki if I have to!"
To be fair, Loki was already present in the periphery, but he's not too good with ignoring open-invitations like that. Particularly the stupid ones which let him cause trouble. If ever there was a God who needed to wear a warning sign with a dozen caveats in tiny print on it, it's Loki. Great guy, but rather prone to destroying your comfort zones, ruining your life (however permanently or temporary) and stomping on whatever self-delusions you might have... all in your best interest, of course, so that you can figure out your problems, get help if you need it, and move forward with a much healthier perspective on things.
...Yes, that may have happened to me recently. Shush.
Thirdly, if I can escape that particular tangent, just because one God likes you, it does not mean that his siblings or other pantheon buddies will. Anubis and Osiris may be your bestest best friends ever, but don't just merrily assume that Hades and Hel wants to hang out and party solely because of your association with two other Death Gods.
I'm well-liked enough by some Tricksters, but I'm not stupid enough to wander over to Anansi and ask for a hug. I don't like spiders. Spiders don't like me. I think that is fairly indicative of how that encounter would turn out, don't you?
Now that I've covered those three things, let's move on, shall we?
How to Tell if You Have a Patron:
Firstly, people with patrons tend to be drawn to items, ideas, or animals associated with their patron deities. I am fond of turtles and hawks (creatures of Hermes') and encountered them often as a child, for example. The tricky bit here is to be aware that there is a difference between an animal representing a patron God and a Totem. I do not have Hawk as a totem, but I run into such birds representing Hermes now and then, for example, while I
do have Turtle as a Messenger Totem
and see turtles functioning as a representation of Hermes fairly often. Here, you have to rely on your intuition quite a bit for the distinction.
Secondly, when your patron thinks you are ready to have them in your life, they usually send signs of some sort - commonly referred to as a "thwap." Those signs can be personal symbols of the deity, such as the caduceus for Hermes, or frequent mentions of the deity's name in unlikely places. As another example, it got to the point where I couldn't turn on the TV, read a book, or go on the internet without seeing something related to Hermes or Mercury. Some Gods will contact you via dreams, as well, or you will meet them while you dream-walk or meditate.
The first time I encountered Hermes during a dream-walking sequence, we started shouting at each other. He wanted me to stay put where he could keep an eye on me, and I wanted to explore the strange new environment I was in. It eventually degenerated down to, "Stay here!" "No!" "Yes!" "No!" "Yes!" "No! I want to go over there!" "YOU WILL STAY PUT." "NO, I WILL NOT AND YOU CAN'T MAKE ME."
As first impressions go, I admit I possibly could have done a bit better. Despite that initial spat, though, we actually get along very well.
Thirdly, if you truly do not want to interact with your patron God, you do not have to. Do not fall into the line of thinking that you have to go against your current beliefs and drop everything once a new deity appears. It's your choice, ultimately, and even Gods tend to respect that. If you're not ready, then you're not ready - most deities will fall back into the background and wait until you're ready to handle them if you react badly to an initial encounter. Some, admittedly, may push you into accepting them, but usually only if it is a change in your life that you really, really need.
Some people have an easier time sorting out who their patron God is than others. For some individuals, it's as easy as meditating and the God in question come to you and outright says, "Hello, you're one of mine. Be a dear and acknowledge me in your life, would you?" On the other side of the spectrum, however, some Gods will only give your hints and nudges in their direction with the idea that you need to figure it out yourself.
When you have multiple patrons, identification depends on a number of things. In my case, my Gods came in a single-file sort of routine. Hermes introduced himself and made himself known, then Loki appeared very briefly to let me know he was present but not active, then Anubis appeared while I was helping with a healing process for a friend and took an interest. Some people, however, get caught up in a sea of deities trying to get their attention and have to find a way to deal with that.
Another thing which should be noted is that not every God that appears in your life is automatically a patron. Kokopelli, a Navajo Trickster, is not one of my patrons at this stage in time, but he does show up now and then to see how I'm doing. We don't really talk or interact much, but he appears to be curious enough to wander over and take a peek at my life when it suits him. Similarly, I share my name with the wife of Loki, Signy/Sigyn, but she is not (as far as I can tell) a patron of mine, either.
Now, I cannot caution you enough about avoiding Fluffy-Bunny Syndrome. For those who don't know what that is, a Fluffy Bunny is someone who thinks that every minor thing that happens to them is somehow magical, God-related, or spiritual.
If your door abruptly slams shut, you can identify the Fluffy-Bunny in the room by looking for the person who automatically assumes that there is a demon in your house and is already starting to exorcise it. A non-Fluffy Bunny will check to see if there's a strong wind coming through a nearby window which would just have easily resulted in the door closing on its own.
I have a
rule of three about this sort of thing, particularly where Gods and patrons are involved. If something happens more than three times in a row, I will tentatively assume that it is not a perfectly ordinary event and consider investigating it further. Less than three, and it's not worth paying attention to.
If you have any questions, feel free to post a comment below and ask!