There are many signs of angelic presence, as mentioned previously synchronicity is a common way angels will get your attention. Feathers, warmth or light going through your body, tingling sensations in your skin (not a bad feeling, but a nice tingling sensation) which is due to angelic vibrations, flickering lights (again, due to vibrations),
Clouds which are shaped like angels are also signs, lovely scents which you cannot explain, animals or babies staring at what may seem to be nothing, angel orbs, repeating numbers, rainbows, physical touch when nobody is there, random but gentle feelings of joy and love, and angelic symbols such as halos, crosses, and wings.
An angel sign is given to you to get your attention, when you receive one of these signals there is always a deeper meaning behind it. It could help you receive good emotions, inspiration, or answers that you are looking for.
It is important to remember that angels are always looking out for you and even if you are not seeing signs they are still there taking care of you. They just do not have any messages to send to you at the present moment. Stay vigilant, watch for messages, and trust in the angels.