You can advice your friend to buy Bitcoin and have keep for long term investment because this is the best opportunity and time to buy Bitcoin and keep and when it rise you make your gain. If you want it to faill to the list before you buy, it seems that you want to lose your opportunity in bitcoin investment. Tell your friend to buy and hold till the ending of this year
But it would be better if the person who will be informed is someone who already understands about investing and Bitcoin and its risks. Because everyone can not guarantee for profit through any investment as long as there is no increase in price as desired. So make sure the person who is given the advice is based on his own intentions, not based on orders from others or ideas from others. Because it will look good when he loses on the basis of his own intentions without having to involve other people in it.