If your Transaction Log file was growing too big and you wanted to manage its size, then instead of truncating transaction log file, you should choose one of the options mentioned below.

1) Convert the Recovery Model to Simple Recovery

If you change your recovery model to Simple Recovery Model, then you will not encounter the extraordinary growth of your log file. However, please note if you have one long running transaction it will for sure grow your log file till the transaction is complete.

2) Start Taking Transaction Log Backup

In this Full Recovery Model, your transaction log will grow until you take a backup of it. You need to take the T-Log Backup at a regular interval. This way, your log would not grow beyond some limits.