Here are some signs that you were close to shifting:
1. Feeling like your body is falling asleep. This is probably one of the most common of all the symptoms. I personally felt this when shifting. But I recommend not thinking about it if you can help it.
2. Legs or arms going numb. This also happened to me and sadly, I screwed it up by moving. So please DONT MOVE.
3. Headaches. Of course, no one wants this symptom but it means that it's working. If you get a headache while shifting it means that your brain is working hard to help you enter your dr. If your headache gets so bad that it is unbearable please take a break from shifting until you feel better.
4. Feeling like your body is levitating. This one was kind of scary, to be honest. But please don't be scared, you aren't actually levitating. And remember, don't open your eyes at all during shifting, unless you are 100% sure you are in your dr.
5. Feeling twitches and tingles. This was very cool for me personally. The first time I came close to shifting I felt tingles up through my body and I kept having twitches in my feet and hands.
6. Hearing/smelling things from your dr. This may not happen for some people, it happened for me and it was amazing! This also might not happen unless you script it to happen. If you don't script it to happen, make sure you are thinking about it while shifting.
Resources used: Amino.com, Wattpad