What should you do when a bit of beer foam adheres to the side of the glass after each sip giving a lace-like effect?

When beer foam adheres to the side of the glass after each sip, creating a lace-like effect, this phenomenon is actually known as "lace." This is generally considered a positive sign, indicating that the glassware is properly clean and that the beer has good carbonation and quality proteins that contribute to foam stability.

Continuing to prepare glassware in exactly the same way is the appropriate course of action because maintaining the current cleaning and washing practices is supporting the desired outcome of great beer presentation. A clean glass ensures that the beer's carbonation is retained, leading to that beautiful lace effect.

Using more soap to wash the glasses, rinsing them more carefully, or immersing them longer in a sanitizing solution might detract from the beer's ability to form a good head of foam. Soap residue can create off flavors or a film that hampers the formation of foam, while over-rinsing could disrupt the cleanliness necessary to maintain that lace, and prolonging sanitization time does not necessarily improve the cleanliness of the glass if it’s already effective. Thus, maintaining current practices that yield a desirable lace effect is optimal.