A straddle is a call and a put at the same strike; a strangle uses strikes either side of spot and costs less. Both profit if the move is large enough, in either direction, to exceed the combined premium. The general structure is covered in straddles and strangles.
The bar is higher here
Because implied volatility is higher, the premium is higher, and the move required to break even is correspondingly larger. Crypto moving a great deal is not, by itself, an argument for buying a straddle — the option is already priced for an asset that moves a great deal.
The trade only works when the move exceeds what was already priced. Which makes it a bet on realised exceeding implied, not a bet that crypto is volatile.
Where the daily expiry helps
With an expiry every day, a straddle can be bought for precisely the window that contains the event you care about, rather than paying for weeks of time you do not want.
That is a real advantage over markets with monthly expiries, where an event straddle carries a lot of unwanted duration. It also means the position decays extremely fast — a short-dated straddle that is wrong is worth very little very quickly, per theta in a market that never closes.
The way it usually fails
Not by the market sitting still, which traders expect. By the market moving substantially and the position still losing, because implied volatility fell at the same time.
A straddle is long vega as well as long gamma. Buy one into an anticipated event and the event resolving — in any direction — can collapse implied volatility enough to offset the directional gain. Being right about the move and wrong about the vol is the characteristic loss, and it surprises people every time.
The structural read
Straddles are most attractive when implied sits low against the asset’s own history and there is a reason to think movement is coming. Reading that requires the whole volatility surface rather than a single implied number — specifically whether the expiry you are buying is cheap relative to the ones around it.