These procedures seem to work well on a 64 bit Windows 10 desktop.
Do regular backups. Disaster or an accident is always a possibility. Backup onto external drives, which are stored away from the computer. Little time is wasted even if planned to be done daily. There are several free backup programs such as Macrium Reflect but the best backup appears to be Acronis True Image which is initially by subscription. It incorporates a modest measure of compression. Use the program also to make a boot media such as a CD or a memory stick. You might need it sometime for recovery or transferring to another device. Select a custom full backup and not a scheduled or incremental version to keep things simple and less subject to error.
To avoid time and space backing up rubbish, use the free CCleaner. Click on the Custom Option, not the automatic option. Avoid wiping the registry (regedit) as the registry takes up little space and some files are shared.
Only use only one antivirus program. If there is more than one in use they can detect each other and cause interference. The most useful is Symantec Norton Antivirus. Do not purchase a 5 device subscription if you only want to service one or two devices. It has a firewall, a site checker, detection of malware, ransom ware and key loggers. A warning can pop up if a site contains malware. All of these functions are available, in mixed quality, from freeware sources. Update the program daily and run a quick scan. A full system scan is time consuming and has never found anything.
Consider these free programs:
For browsers it is suggested that you use Firefox and Google Chrome. The latter is quick and can provide bookmarks.