One "strategy" that works really well for me is to go to bed early, preferably around 9-10 PM, and decide for yourself that you are going to wake up after a dream and remember it as much as you can - then fall asleep again, and while falling asleep you repeat to yourself that you are going to recognize whatever dreamsign you may have spotted earlier.
Really make sure you are determined about it, and repeat firmly to yourself that you are going to recognize your dreamsigns if they appear in the next dream.
You could even use a "mental mantra" in a sense, where instead of using words you imagine yourself seeing your dreamsigns and exclaiming "this is a dream!" by association - almost a bit like acting.
You pretend that you see a dreamsign and then try to convince yourself that you are actually surprised by it, like an actor, and tell yourself that this is a dream, since you saw that dreamsign.
Also, make sure that you actually believe in yourself.
If you feel that you have been unsuccessful for a year then you are probably doubting your own skills.
You need to convince yourself that you can in fact become lucid, and expect to spontaneously tell yourself "I'm dreaming now!" in your next dream.
It might not work instantly, but if you keep believing in it then your brain will be like "wtf, he believes in this so much that it must be true".
Placebo effect!

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