The ornamental design for a golfswingtrainingaid, as shown and described.
FIG. 1 is a top perspective view of my golf swing training aid, the grip end of a golf club being shown in broken lines for illustrative purposes only and forming no part of the claimed design;
FIG. 2 is a side elevational view of my golf swing training aid;
FIG. 3 is an opposite side elevational view of FIG. 2;
FIG. 4 is a front elevational view of my golf swing training aid;
FIG. 5 is a rear elevational view thereof;
FIG. 6 is top plan view of my golf swing training aid; and,
FIG. 7 is a bottom plan view thereof.
The broken line showing is included for the purpose of illustrating and forms no part of the claimed design.