Note grace at the begining of a piano piece

[Tomas Valusek]

Hello,

I'm learning to use LilyPond and as a pianist I use template introduced 
in section 3.2.4 of the User Manual. A piece I'm now trying to copy 
begins with note grace in right hand. Section 6.4.7 says: "A score that 
starts with a \grace section needs an explicit \new Voice declaration, 
otherwise the main note and the grace note end up on different staves." 
Since I'm not (yet) familiar with the LilyPond concept of staves and 
voices, I'm not sure what to write to the beginning of the \upper 
variable in template 3.2.4. Can you help me? Many thanks and sorry for 
bothering you with quite a number of my posts.

Tomas Valusek