The locals head to their local Lido to escape the heat. Even though a few have a spit of sand, you will mostly find a nice lake side pool, a restaurant, bathroom/dressing facilities with umbrellas and lounge chairs for rent.   Almost every town has one.

Lido di Cernobbio

Piazza Risorgimento 5

Cernobbio

Gorgeous views of the lake of course, but also Villa Erba right next door. The lido has a baby pool and a large, adult pool. The restaurant has excellent pizza.  Get there early on Summer weekends for a spot!  Opens at 9:00am, until 7:00pm.  LidodiCernobbio.com

Lido Villa Olmo

Via per Cernobbio, 2

Como

This one is big, with two swimming pools and a natural little beach.  They have parking, which is a huge plus, but get there early. Opens at 9:00am, until 7:00pm.  LidoVillaOlmo.it

Lido di Moltrasio

Via Regina 27A

Moltrasio

This lido boasts a two-tiered diving platform into the lake and a buzzing restaurant. It is right near the Grand hotel Imperiali in Moltrasio.  No pool! but a lake side area with umbrellas & lounge chairs to rent for the day.

Lido di Lenno

Via Comoedia, 1

Tremezzina / Lenno

Lido di Lenno also has sand and is near Villa Balbianello, one of my favorite lake "To Do's.  This is were you would get on board a small shuttle boat to take you over to the villa for a tour.  There's a restaurant, facilities, umbrellas & lounge chairs for rent.  lidodilenno.com