Hi Maddison I suffer from anxiety and although I rarely get anxiety attacks now, I still find them frightening and debilitating when they happen.
Tried and tested coping mechanisms are the best. Slow and regulated deep breaths; in through the nose and out through the mouth. Finding somewhere comfortable and quiet to sit until they pass with some relaxing background music always helped me.
I think of an anxiety attack as a huge wave that I know is going to hit me but there's nothing I can do so, I imagine myself standing and letting the water crash over me, safe in the knowledge that when it goes back out to sea, I'll be wet through but I'll be OK.
Knowing the reason/source of your anxiety is helpful and if it's due to a specific incident as mine was, as time passes often the frequency and severity ease too.
Bach's Rescue Remedy is good as are Kalms although with the latter it does take a few weeks before you really feel the benefit.
I hope this helps.