Nobody can tell you exactly when to buy. In comparison to the last few months the price is relatively low , you can buy some now and just keep adding to that stack every month. This way you can average the price you bought for.
Only you could answer that question because you are the one who have are going to used your own funds and buying or either selling bitcoin is a personal choice to us. We should not depend our decision on the opinion of others despite of the risk it would take, we should need to always ready ourselves on the outcomes of our own decision when it comes to starting an investment to bitcoin or even trading.