Log files are as important as the data file as they are there to preserve data integrity.
The only way to truncate (which will not reduce the size of the file on disk) is to take a log backup (presuming you are running in full recovery model).
As mentionned by Andrew, you may want to run more frequent log backup (which will mark the VLF as re-usable and prevent from log file becoming too large).
If you do not need log backup (it's ok to lose as much data as your full/diff backup interval) then you can put the database in simple recovery model and you won't have to care about the truncation of the log file.
If your intention was to reduce the size of the log on the disk (Shrink) then it's a different discussion and this is not something I would recommand automating (if the log constantly grow to this size it's because it needs that space so shrinking it over and over won't give you any gain and will consume ressources for nothing).