This is the other option. Just pour from the fermentor. I've been using this method for years along with over building a starter once in a while to save a small amount of fresh yeast.
https://www.homebrewtalk.com/forum/threads/simple-yeast-storage-procedure.519995/
Yep.
My entire yeast management regimen goes like this...
1) Acquire fresh yeast by either purchasing a new commercial package or harvesting from a bottle of beer.
2) Make an initial starter from yeast acquired in step 1. Save 30-50B cells along with the starter "beer" to a sanitized 8 oz or 1 pint mason jar to inoculate a subsequent starter at some undetermined future date.
3) Ferment a batch of beer with the balance of the starter. Once beer is packaged from primary, save a pint or two of slurry from the fermenter to be repitched as-is into another batch within the next 2 months. If I have no upcoming use for the fermenter slurry, I won't bother saving any. I try to schedule brews so that I get at least one follow-on brew using saved fermenter slurry. I've done as many as 4 in a row from the same strain (starter > slurry > slurry > slurry).
4) Make a fresh starter from saved starter yeast (or newly acquired yeast) and repeat the process.
Additional notes:
*Saved yeast from a starter should keep in the fridge for at least 6 months, often much longer. I revived 15-month old yeast once. As the cells die off, they will turn a color that resembles peanut butter. As long as there are still some white colored cells remaining, you should be able to revive it.
*This is personal preference, but my max time for saving fermenter slurry is about 2 months. If I haven't used it by then, I'll likely dump it and make a fresh starter when I'm ready to use that strain again.
*Acquire new yeast when the yeast you have is no longer fermenting the way you like it (picking up undesired flavors, attenuation too high or too low, etc.). My current WLP028 strain was last purchased in late-2014 and my current WY2124 strain was last purchased in mid-2015. I've brewed with both of these in the past few months and they are still producing great beer, so I will continue to use it and not replace it until something changes.