for that i always suggest everyone to buy in steps. you first come up with a price range that you speculate is the bottom or won't go lower than that. for example $1900 to $2100. then you start placing all your orders.
majority of them in this range. then you place some lower orders but smaller for example you place $8000 in total of 10 orders in that range then place 2-5 orders of total size $1000 in $1800 to $1900.
also you place some orders above the highest price for example at $2200 you place 2-5 orders of total size $1000.
As a variation of this, you could also go the route of dollar cost averaging and simply invest over the course of a predetermined timeframe regardless of price (say, USD 500,- each day for 20 days, or USD 1000,- each week for 10 weeks). This way you can even out large swings, without trying to guess a possible bottom. Either way I definitely wouldn't invest the lump sum of USD 10,000,- at once.