Move up a floor (or multiple floors). Signal tends to be better on higher floors, as you're able to clear obstructions closer to ground level. If you're in a basement, moving up to the ground floor can help immensely.
Move closer to a window. Cell signal has an easier time entering a building when it’s not blocked by the construction materials, like brick, block, siding, or sheet metal, that the building is made of, so windows are typically areas where you'll receive stronger signal than behind a solid wall.
Find out which direction your closest cell tower is. Goto a site such as
speedtest test the download 1-3 times, move the hotspot to another location, do the test again. Try this in as many locations as you can. At least once North, East, West, South. If you find the best location, but it is causing you to have no WiFi signal to where you need the internet or it is weak, a simple and inexpensive WiFi range extender will solve this problem.
Reorganize your space. Certain objects in your home or office tend to block signals, like metal filing cabinets, refrigerators, decorative waterfalls, and solid furniture. Rearranging these objects so they’re not between you and the outside cell signal can help.
Open your window. If your windows have an energy efficient coating applied to them, then unfortunately it also blocks cell signal, so opening your window can allow the cell signal to penetrate into the room.
Go outside. The construction materials that make up the walls and roof of a building block cell signal, so going outside should allow you to receive a stronger signal from the local cell towers. Leaving a hotspot outdoors would require a protective box to keep it from rain/elements.
Remove trees & bushes. Trees, bushes and any other living thing is made up of water, which blocks cell signal to varying degrees. If possible, trim unnecessary branches or remove overgrown bushes to create a more open surroundings.