(a) work out your party's power level experimentally.
(b) 6-9 encounters per long rest, and 2-3 per short rest. If this doesn't fit your pacing, consider gritty rests, it makes it easy.
(c) start using alternative encounter building.
The easiest is to add up the CR of monsters and compare to the sum of levels of the party divided by 4. Past level 5, this is a shockingly good proxy for the complex DMG encounter XP building math.
Monsters =~ PCs/6 -- easy
Monsters =~ PCs/4 -- moderate
Monsters =~ PCs/3 -- hard
Monsters >= PCs *0.4 -- deadly
(The largest error this has is with CR 1 and under monsters, which you tend to use in larger numbers, so you might want to fudge it: Replace CR 1 with 6/5, CR 1/2 with 4/5, CR 1/4 with 3/5 and CR 1/8 with 2/5 of a point).
Once you get used to doing this, you'll start noticing your players with their gear and optimization are too strong. Just bump up the effective level of the party -- which corresponds to boosting the encounter budget in a linear way.
So a party of 5 level 10s? Sum is 50.
CR budget by difficulty is:
Easy: 8
Medium: 13
Hard: 17
Deadly: 20
If you want to build "scenes" in a similar way (a scene is a set of encounters bundled together such that a short rest between them would lead to consequences -- aka, some kind of failure or complication), you have a 4 point budget in a "moderate" scene. An easy scene has 2-3, a hard scene has 5-6, a deadly scene has 7-8.
Toss in encounters in that scene. Each Easy is worth 1, Medium 2, Hard 3 and Deadly is worth 4. (We don't add up CR here because easy fights drain way less endurance than their CR sum would indicate).
String together 3 scenes into a chapter (a chapter is a set of scenes/encounters where taking a long rest before completing them would lead to consequences -- aka, some kind of failure or complication). 2 scenes make an easier chapter, 4 makes a harder one.
(This doesn't require a railroad. Suppose you have a shrine to a demon they find in the wilderness. In gritty rests, it could be a scene. There is an easy encounter of undead outside, a medium encounter of uneasy spirits inside, then a hard encounter of a demon appearing to prevent to shrine from being purified. If the players disengage and take a night's rest, the awakened shrine spawns the demon and more undead and attacks if the PCs are still in the area. During that attack, a demon-spirit rides an undead and flees, setting up a new seed of evil elsewhere. Consequence, not railroad.)