Recently I have been taken to work by a taxi driver who started asking me questions about the company I work for when hearing about my destination. I didn't mind and I replied and when he heard that I work in the Human Resources Department he was so happy and asked for advice about building his resume.
His question was - if I apply for the position of Help-desk Analyst should I mention that I was a taxi driver in the UK for a few months or it affects me in a negative manner? My reply was - write in your resume relevant information for the position you are applying for.
In his case, he was applying for a position requiring fluent English. I told him to mention the taxi driver position, but the emphasis should be on "UK", not on "taxi driver". We hire people speaking great English and if he mentions that he has been working in the UK, this obviously shows that he knows some English, the level needs to be determined later on, but this information will at least convince us to call him for an interview.
So, write in your resume all the information relevant for the position. If the position is that of Gardener, you have never worked before as professional gardener, but are passionate about gardening and your own garden, mention that and put less emphasis on your other positions as bartender, flight attendant or whatever. Mention those to avoid questions like "What did you do during these two years that don't appear in your resume?", but don't offer too many details.
Focus on the position requirements and offer as many details as you can on those.
For example, if you are Computer Science Graduate, work currently in Finance, but hope for a position of Software Tester, mention your studies, offer some details relevant to the position you want, and also mention all the extra training that you have done by yourself or the books you read, anything relevant showing that you are preparing for the position you want. Mention your current position only by name, time frame and compress your current responsibilities if not relevant in 1, maximum 2 lines, just to show that you are working, but that's it. They will ask if they want more information.
The purpose of the resume is to buy you an interview. If you give too much irrelevant information, chances are they won't even bother to read it. Don't lie in your resume (NEVER!!), because information can be verified, but limit the volume of irrelevant information.
Good luck and take care,
Geo