Reality checks is what helps me the most. Looking at my hands and focusing on them has 'saved' me a lot of times! Also you should try to stay calm those first moments and stabilize your dream. For instance I always shout "stabilize!" and "clarity!". They both work for me and it prolongs my dream I have been there before, when the dream fades and there's nothing you can do about it to stop it. But even then I have managed to DEILD a couple of times (I'm also a beginner). If you don't know what it is look it up on this forum
Hope this helped a bit