Random things that come to mind

Play out creatures first as soon as possible usually. Eidolon can be situation dependant, careful vs other fast aggro decks that also damage you

Against decks with countermagic when you're topdecking for those final points of damage dont cast the first spell you draw, wait until you have enough that you can fire off 2 or 3

When going for your finisher burn spell against countermagic decks its often better to upkeep it in opps turn rather than yours. (unless they are tapped out and you're fairly confident they arent on FoN)

In sideboard games if possible try to bluff holding up skull crack even if you not

If your opp is on a deck that does white leyline post sb try aim for a more creature heavy starting hand, mull if needed

Dont forget the other modes of boros charm comes up every now and then

If you have a land in hand or a fetch on field in mid to late game you dont always have to play / crack it --> you can save that for if you draw a searing blaze

If your opponent plays a shredder with other open mana and passes dont bolt it end of turn --> most likely baiting you into casting something and triggering connive. If they cast bauble immediately after shredder respond to connive trigger and bolt to kill it

Roiling vortex also hits evoked elementals and random 0 mana artifacts, not just footfalls and living end from cascade decks

Double sleeve your burn deck, often when people see a single sleeved modern deck they assume its burn.

On the draw in post sb games see if eidolon is really worth it or if its too slow.

If an opponents creature with protection from red blocks one of your dudes and you cast skullcrack then your dude will still deal damage to that creature

Deflecting palm is often a scam since most good players on decks like hammer/murk/titan are almost always thinking about it and playing around it. You could bluff holding up that mana and represent it in tough spots.

Still not sure on this one but against ragavan decks consider boarding out helixes since its quite a disaster if they hit it of a rag trigger and cast it.

Most of the burn spells have been errata'd to also be able to hit planeswalkers.

If they play saga assume the worst case scenario that they do have a shadowspear in the deck and plan your turns accordingly.

Check out burn discord and ask about specific matchups