Currently the price of bitcoin is falling, and actually this is the right time to buy bitcoin, then be patient waiting for the increase in bitcoin prices, and I'm sure bitcoin will rise again in the near future.
But don't forget to take that investing plan with a pinch of salt, always.
Indeed, once prices had fallen for any investing instrument, the wisest move is to buy. But before you do so, check with your actual finances. Do you have enough cash to afford an investment? And if so, are you ready to loss it and can afford to loss it? Should your investment fail, do you have a fallback?
These should always be considered before jumping on board. Truly, bitcoin holds a lot of possibilities and a lot of people out there believe in the profitability of the coin, but please don't throw caution in the air.