"Your timing should never be dictated by high prices. High prices were never a timing signal to sell a stock. Just because a stock is now selling at a high price does not mean it won’t go higher....

....I never buy a stock on declines, and I never short a stock on rallies"

Buying stocks as they made new highs and selling short as they
made new lows was a contrarian point of view in Livermore’s day. He
let the market tell him what to do. He got his clues and his cues from
what the market told him. He did not anticipate; he followed the
message he received from the tape. Some stocks keep making new high
or lows for a very long time, and therefore can be held for a very
long time.