Best strategy is to play as much as you can. More pink chests will let you get additional radars and also more peronamins. Also go and clean-out any inactive players, i usually delete 10+ days inactive.

Save any non-timed consumables until the second phase as well since there's an additional n slayer. Pray to rngesus for e-gacha. Also only use glasses on 5 step ups.

Depending on what your lvl is the event can be much more challenging. Sadly there's nothing that can be done short term to fix this and is more of a continual advantage you'll build up over time.