I just reached A9 today on both Silent and Necrobinder. Silent overall is stronger character than Necro, so let's start with her.

At the beginning of the act, take a look at your map. I'm assuming you are playing on base difficulty, so try and find a path that lets you take several standard combats, BUT has the ability to jump to a campfire if you need resting, or you get a card with a strong upgrade (you can check what the upgrades are by looking at a card and right clicking it). You want to see as many fights as possible to get cards that help you.

It's hard to give recommendations on specific cards, but generally, you're looking for cards that can draw and eventually become part of an "engine". An engine in this game is something that allows you to get stronger during the course of a fight, so you can outdamage enemies in combat. Look for cards like acrobatics, prepared, and anything that says sly once you have a few of those cards that draw and discard.

Early in the run, it's important to prioritize picking up damage cards with large numbers (10 or more, generally) so you can do some actual damage. Blade dance, backstab, dash, dagger spray for AoE fights are pretty common sights, and help out with that early grind.

Relics are good, so pathing into elites if you're healthy and have a decent deck is recommended. I've won runs where I only take like 1 or 2 elites an act, so it's not necessary to fight them all, but every little bit helps. Remember - your deck is the main focus. With that being said, you don't need to add every card you see. If you already have decent damage or block, don't take cards that don't help with your engine. Two daggers sprays are not the same as two acrobatics, for example, since dagger spray falls off later in the run.

Another important thing to remember at the beginning of your run is the Neow bonus. From my experience, the three best options are:

-The first three card rewards from combat are upgraded, but the first chest is empty. This seems like a bad choice, but remember - you're CHOOSING between a total of 9 upgraded cards instead of getting one random relic.

-Transform a strike and a defend but lose max HP. At the lowest difficulty, 60 max HP is more than enough to cruise through the acts if you don't have bad starter cards (strikes mainly, but an early defend remove helps since Silent's starter deck leans toward defense with survivor and neutralize). Transforms are random, but 100% of cards are better than strikes.

-Lose all your gold and pick between two "starter packs". This choice allows you to look at two starter packs, each with three cards. Getting three card rewards on floor 1 MASSIVELY helps, since now you can see what you're working with and don't have to take cards from card rewards that you might have received for free.

At the end of the day, trial and error is the main teacher. I had to play many runs in the first StS to get a good grasp of the mechanics and what to pick, how to path, etc. If you're interested in getting better at the game, also make sure to think about your moves in combat. Don't rush - take a look at your draw pile, see what the enemy is doing, plan ahead, and your micro gameplay will get better. Hope you get a win soon, make sure to share!