Generically speaking, the only simple tasks for an end user of a tube amp are:
1) periodically check the status of all tubes using an appropriate tube tester;
2) adjust the bias of the output tubes using a voltmeter. This step may vary with the amp in question. Some amps automatically bias the output tubes or may have another procedure to follow.
If you don't have one, get an owners manual for your amp. Even for used equipment these are often available as a free download if you look around the internet. People also often sell them on eBay. If you are technically inclined, you may also want to obtain a technician's service manual.
There are further tweaks and modifications a person can do, but they often require technical skills and/or additional test equipment. It is tough to be any more specific without knowing the make and model of your amp.
1) periodically check the status of all tubes using an appropriate tube tester;
2) adjust the bias of the output tubes using a voltmeter. This step may vary with the amp in question. Some amps automatically bias the output tubes or may have another procedure to follow.
If you don't have one, get an owners manual for your amp. Even for used equipment these are often available as a free download if you look around the internet. People also often sell them on eBay. If you are technically inclined, you may also want to obtain a technician's service manual.
There are further tweaks and modifications a person can do, but they often require technical skills and/or additional test equipment. It is tough to be any more specific without knowing the make and model of your amp.