If it's too expensive, then wait until you think it's cheap... I know the price of BTC tends to increase every year, so if you feel this price is very high, it doesn't necessarily mean that next year's price will be below the current price... you yourself should realize that there is nothing accurate in every prediction, so if you are afraid of buying too expensively for now, DCA is the solution...
Many have discussed DCA here, and its purpose is to avoid buying BTC at a price that is too expensive...