As many here have noted, Dollar Cost Averaging is the way. Remove the emotion and temptation to try (and certainly fail) to time the market.

nostr:npub1ex7mdykw786qxvmtuls208uyxmn0hse95rfwsarvfde5yg6wy7jq6qvyt9 and nostr:npub1xkere5pd94672h8w8r77uf4ustcazhfujkqgqzcykrdzakm4zl4qeud0en, among others, make this very straightforward and largely fee-free.