It's all about luck, just keep trying till you get it eventually

Or if you want to be certain that you'll get it then you should learn how to RNG Abuse, but that's pretty complex and will take a while to pick up so make sure you actually want to learn it before trying, it's not easy. xD If you want more info then check

__here__
Sorry I know you posted a link and everything but while I was replying I said I'd ask even though my question will undoubtedly be answered in the link which I will read after I post this is RNG abuse in-game or do I need to use something outside of my DS to do if its quicker(been breeding chomp's for 2-3 days now closest I got is x/31/x/x/x/29) I will definitely try it out

as for my earlier problem, after about an hour of reading I deduced that if 2 parents hold 2 power items the baby has a chance of inheriting only 1 of the parents stats not both and its 100% not 50 so I'm guaranteed 31 in 1 stat after that I just have to hope that the 2nd parent passes on the 2nd 31 so my best chance is power item on one parent and everstone on the other 1 and hope the 2nd stat passes :L I think I have like a 19% chance of that happening but its better than nothing I guess about the 6th garchomp I raised to lvl 50 had 182 atk and 167 speed :/ I would have prefered 180atk instead of speed tie'ing with jolly 252 salamence and non timid floatzel at 169 speed garchomp's only real threat is garchomp,latios,weavile,starmie and scarf'd porygon-z

apologies I am notorius for going off topic but thanks for your help! again! I'll have a look into this RNG thing now