If you like to use miniatures at the table, I recommend you make some measuring sticks. DM Scotty has a great video on how do this:
https://www.youtube.com/watch?v=XTT1ZU5pDBg
It allows you quickly measure movement, especially helpful if you ware playing without a grid.
Also, for spell effects, Macrame Rings in various sizes to measure spell effects. DM David has good post about this:
http://dmdavid.com/tag/some-new-favorite-dungeon-masters-tools/
I found a cheap alternative to Macrame Rings. I got brass rings from CreateForLess:
https://www.createforless.com/buying-guides/crafts/brass-rings.aspx
Flight Stands for miniatures. I really like Dr. Wizards Elevation Indicator:
http://www.emeraldsemporium.com/Elevation_Indicators.html
For my homebrew campaign, I use RealmWorks and HeroLabs to run my game. When running published adventures, though, I just use the book and keep things simple. I have a sheet with the characters armor class and passive perception scores. I've stopped using initiative tents and the Paizo Battle Pad that I used to use. The Angry DM convinced me I was making things more complicated than I needed to and now I just use a sheet of paper to track initiative and hit points when not running combats from Hero Lab. See the Angry DM's post:
http://theangrygm.com/manage-combat-like-a-dolphin/
If you are playing 5e and use the inspiration mechanic, I recommend having a physical object to give a player that represents inspiration. It help players remember to use it, either for themselves, or to give to other players when needed. You can buy them (e.g.
http://www.thingiverse.com/thing:1545591) but I just use some cheap, large, shiny plastic pirate coins from the dollar store.
Similarly, get some funky large or specially colored dice to represent buffs like Bardic Inspiration to remind the players that they have it to use and roll.