Here just a few anectotal tips (no trading knowledge, sorry).
One is that you probably will be too scared to sell, because you think the dollar will drop further, and only gold will keep the value….-> then sell.
Other investments will also look risky, and nobody will have any confidence in stocks, even though they will sell at P/Es of 5 (solid forward earnings)…-> your chance to shift from gold into stocks, real estate, or if you trust your politicians: bonds.
People will go absolutely crazy about buying gold to protect their hard earned dollars, since they haven’t bought any gold yet. In 1980 the coin store in La Jolla had a line of 100 people waiting….-> sell your gold to some of these fanatics.
The inflation adjusted price of $850 (in 1980 dollars) is probably a good target. But use your own inflation statistics, not the government’s, haha.
If you notice that you missed the peak, e.g. after a huge price reversal, I suppose it’s better to sell, too. Better late than ride it all the way down again. (Like real-estate now with 10-20% below the peak).
Any other suggestions?