Free things to do in San Francisco are not hard to find once you stop treating the city like a visitor with a checklist.

October is especially generous because some of the month's biggest experiences happen outdoors or in neighborhood public spaces.

Fleet Week is the obvious starting point.

You do not need a ticket to watch the air show from public waterfront areas, see the Parade of Ships or enjoy much of the atmosphere around Fisherman's Wharf.

The tradeoff is crowds, so arriving early and using transit can save both money and patience.

October's Walktober activities are another easy win.

Guided and self-guided neighborhood walks turn stairways, parks, murals and architecture into the entertainment, and the price of admission is essentially a comfortable pair of shoes.

San Francisco is one of those rare cities where a walk can legitimately compete with a paid attraction.

SF Open Studios gives art lovers a chance to visit working artists and creative spaces around the city through late October.

Neighborhood festivals and Sunday Streets events also offer free entertainment, people-watching and a reason to explore commercial corridors you may not normally visit.

Then there are the city's everyday bargains.

Golden Gate Park, the Presidio, Ocean Beach, Crissy Field and the Great Highway area can fill an afternoon without requiring much more than transportation and maybe lunch.

Pack your own coffee or picnic and San Francisco suddenly becomes a surprisingly affordable place to spend a day.

Libraries are another overlooked source of free programming.

Branches around the city regularly host talks, children's activities, workshops, exhibits and community events, many of which require no advance planning.

For one of the best cheap evenings in town, choose a neighborhood, walk its commercial street and give yourself a modest food budget.

A bakery treat, dumplings, a slice of pizza or a cup of hot chocolate can turn an ordinary walk into an outing without the price tag of dinner and drinks.

The SF Brief rule for October: do not confuse spending more with experiencing more.

Pick one free city event, one outdoor destination and one inexpensive neighborhood stop.

You can have a very San Francisco weekend and still have money left on Monday.