I am attempting to save some tomatoe seed this year and this is the process I am following:

First select the most appealing

fruit.

This should supply you with a

good crop for next year.

Next, we remove seed and

place in a clean container.

Preferably, (they say)

glass so you can watch
the seeds for any

problems.

Cover with paper towel

and hold in place with

elastic band. This will

help impede odour and

keep fruit flies out.

Place these in a warm

out of the way location.

Now we wait 2-4 days for fermentation. Fermentation can be quite smelly. It is suggested that you keep the containers in a place that you will not pass too often.