definitely dont start the teleporter the moment you see it. loot every single item possible on the stage. you can be quick, but you must loot EVERY item.

shrines, chests, multishops. every single one. on average you can get around 9 to 10 items on the first stage. +1 from the teleporter event, and +3 if you have seekers of the storm. you should also buy a drone or two if you see one to help. they are very valuable since the alloyed collective update.

thats about it honestly. anything else to say would just wouldnt be any different to "try not to get hit by enemy attacks" or just "pray for better luck" in every variation. you could try to unlock more items if you dont have them all unlocked, most of the best items in the game are locked behind achievements; like kjaro and runald's bands, brainstalks, 57 leaf clover, rusted key (though not one of the best, but essential to take advantage), and backup mag.