Where to find Marni at H&M

Marni at H&M, the latest designer collaboration with an affordable retailer, launches at 8 a.m. Thursday at six H&M stores in Manhattan.

No Long Island H&M stores will be stocked with the coveted merchandise, but the two stores closest to Penn Station will have the goods (and probably the biggest crowds.)

Locations:

Midtown

435 7th Ave. at 34th St.

1328 Broadway at 34th St.

Downtown

111 5th Ave. at 18th St.

515 Broadway between Spring and Broome

Uptown

150 East 86th St. at Lexington Ave.

640 5th Ave. at 51st St.

Shopping tips:

1. Know what you want in advance. There's no time for thinking, just grabbing. View the collection here.

2. If possible, bring a friend. An extra pair of eyes and hands will be a huge help in navigating the crowds.

3. Arrive early. It's common for shoppers to line up long before the stores open.

4. Prioritize. Smaller sizes tend to go first, so head straight for the items where size matters most. Jackets and pants are tougher to alter, while loose dresses and tops can often still work tucked in or cinched with a belt. Have a very limited budget? Snatch the more affordable accessories while everyone else worries about the clothes, and you'll most likely end up happier with your loot.

5. If you have the time, linger. Merchandise will disappear quickly from the racks, but once overeager customers are finished in the dressing room, pieces they decide not to buy will become available.

6. Before you head to the register, pause. Lines will be long, regardless. Make sure you didn't become greedy in the heat of the moment and you're buying items you will actually wear. Keep receipts just in case.