Adverbs always go AFTER the helping verb (auxiliary) but BEFORE the main (non-auxiliary) verb:
I was always tired.
I always took a long time.
I was always taking a long time.
I have always taken a long time.
I always have a good time.
I will always have a good time.
I always was tired.*
I took always a long time.*
I was taking always a long time.*
I have taken always taken a long time.*
I have always a good time.*
I will have always a good time*
I just typed this into a student paper and then created a macro using the program ShortKeys. It is a very good program, well-worth the $24.95, and better than my previous MS Word Proofing Tools method (see here for my blog post on poor man's macros). To follow up, when my office upgraded to the newest version of Microsoft Word, I lost ALL of my macros that I had built into the AutoCorrect feature of Word--I felt like the Microsoft Corporation had somehow stolen something very precious from me. Luckily I kept a file that had all of my macros in it, so I was able to paste it into ShortKeys.
For the record, ShortKeys has not paid me to endorse their software, but I still love it.
Also, you can say, "I will have always a good time" and people will understand you, but it's that tiny slip that flags you as a non-native, and it does sound awkward.
Until next time, have a good one and good luck out there!