Need help with my Strength Build

So this is the first time I have played a dark souls game, I played dark souls 2 a little bit but didn't even get to the 2nd boss. Anyways currently I want to do mostly a strength build but I'm not sure what stats to prioritize besides strength. I have 30 str right now with 20 in both VIG and END. I want to be able to use great shields with a great sword so I'm not sure how many points I should be putting into VIT. If I'm going for an extremely heavy build with great shield and great swords, along with heavy armor is it worth it to try to stay under 70%? Also when should I stop leveling strength, and any advice for leveling stats would help, thanks!