Core Upgrading Gear and Weapons

This is a tread i wanted to put up a long time since i fail alot in upgrading my gear and weapons. I've heard that to successfully upgrade your items you can;

1. Save up alot of cores and one day spam all the cores on an item and hope for the best.
2. The other is to try an upgrade no matter if it fails or succeeds till it reachs your desired +15

How the question I am throwing out to you all is what are you tricks, tips or whatever works for you in getting your gears and weapons to +11 and above? Thanks

1. Don't mass upgrade all in one day.(Only do this if its at +0 and u have a bunch of cores)Try spreading out when u upgrade an item. If it fails, then stop upgrading and try again later, vengeance upgrading only leads to even more rage.
2. (I heard this from other ppl) Try upgrading something else u dont need upgraded, and if it fails multiple times in a row, then try upgrading the item u want to upgrade.
3. Use enhanced cores. Believe in the power of what the game says is a higher chance of success.
4. The expensive way: buy perfect cores =.=
5. The less expensive but rare way: get safeguards

Thanks alot brah atleast someone answered, ima try it out

Just want to say that mass upgrade costed me 200m to +9 my redos blade and 400m to +9 my lyncan :((

lol, the other option will lead u nowhere and will take forever...just sayin

mass upgrade: 400m to plus 9 3 sets (sg, tg and mystic).

1-6, 100% success, use echs
7-9, spam!!! lol

I just upgrade until I get an item to +10. Once I have the item +10, I roll the dice and upgrade only when it rolls 99x (with ECHs). If I'm feeling lucky, I'll just upgrade with regular UCHs until +11/+12, THEN start rolling.

Results:

1. 500m and 5 SGH = +15 SIGMetal BL boots & gloves (3 SGH) and +15 Osm 40 DMG Blade (2 SGH)
2. 700m and 10 SGH = +15 SIGMetal FB boots (4 SGH) & gloves (6 SGH)
3. 300m and 4 SGH = +15 SIGMetal 40 DMG Blade