Grams a month: cost-averaging into gold
Buying a fixed amount on a fixed schedule removes the hardest decision in investing, which is when to buy.
The problem with waiting for a dip
Almost everyone who intends to buy gold spends a period waiting for a better price. Sometimes the better price arrives. Often the market moves the other way and the wait becomes its own expensive decision.
Nobody reliably calls tops and bottoms in a market driven by interest rates, currencies and geopolitics at once. Planning around the assumption that you will is optimistic.
How averaging works
You commit a fixed sum on a fixed schedule, monthly for most people, and you buy whatever that sum buys on the day. When the price is high your money buys fewer grams. When it is low it buys more.
Over time your average cost per gram settles below the average price across the period, because more of your money was deployed at lower prices. You are not predicting anything. You are simply refusing to concentrate all of your risk on one date.
What discipline actually looks like
The hardest month is the one where gold has just risen sharply and buying feels late. That is exactly the month the plan exists for. The second hardest is when it has fallen and buying feels foolish. Same answer.
A plan you follow through both of those is worth more than a better plan you abandon.
Reviewing rather than tinkering
Set a review date once a year. Check whether the monthly amount still fits your income and whether your overall holding has grown beyond the share of savings you intended for gold.
Between reviews, do nothing. The strategy works because it is mechanical.